$OBK
Origin Bancorp Inc Stock $obk

$obk Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000151691221000019 Filed on March 02, 2021

Income Statement

Concept	2020 Q4	2020	2019 Q4
Revenue	$59.42M	$228.7M	$56.72M
YoY Change	4.77%	0.71%	6.9%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$1.700M	$5.800M	$1.700M
YoY Change	0.0%	7.41%	6.25%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$7.603M	$37.17M	$12.62M
YoY Change	-39.77%	-30.36%	14.79%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$21.98M	$44.35M	$16.00M
YoY Change	37.38%	-33.35%	0.62%
Income Tax	$4.431M	$7.996M	$3.175M
% Of Pretax Income	20.16%	18.03%	19.84%
Net Earnings	$17.55M	$36.36M	$12.83M
YoY Change	36.84%	-32.52%	-2.66%
Net Earnings / Revenue	29.54%	15.9%	22.61%
Basic Earnings Per Share	$0.75	$1.56	$0.55
Diluted Earnings Per Share	$0.75	$1.55	$0.55
COMMON SHARES
Basic Shares Outstanding	23.51M shares	23.37M shares	23.48M shares
Diluted Shares Outstanding		23.51M shares

Balance Sheet

Concept	2020 Q4	2020	2019 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.432B		$832.7M
YoY Change	71.91%		15.2%
Cash & Equivalents	$377.2M		$291.5M
Short-Term Investments	$1.054B		$541.2M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$81.76M	$103.4M	$80.46M
YoY Change	1.62%	-1.05%	7.26%
Goodwill	$26.74M		$26.74M
YoY Change	0.0%		0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$7.628B	$7.628B	$5.325B
YoY Change	43.26%	43.27%	10.43%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$88.00M	$84.90M	$69.60M
YoY Change	26.44%	21.98%	105.92%
Deferred Revenue
YoY Change
Short-Term Debt		$63.90M
YoY Change		43.27%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$88.00M	$84.90M	$69.60M
YoY Change	26.44%	21.98%	105.92%
LONG-TERM LIABILITIES
Long-Term Debt	$157.2M	$160.3M	$9.900M
YoY Change	1487.88%	1519.19%	3.13%
Other Long-Term Liabilities	$0.00	$0.00	$0.00
YoY Change
Total Long-Term Liabilities	$157.2M	$160.3M	$9.900M
YoY Change	1487.88%	1519.19%	3.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$88.00M	$84.90M	$69.60M
Total Long-Term Liabilities	$157.2M	$160.3M	$9.900M
Total Liabilities	$6.981B	$6.981B	$4.725B
YoY Change	47.74%	47.74%	10.62%
SHAREHOLDERS EQUITY
Retained Earnings	$266.6M		$239.9M
YoY Change	11.14%		25.22%
Common Stock	$354.9M		$353.0M
YoY Change	0.52%		-2.12%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$647.2M	$647.2M	$599.3M
YoY Change
Total Liabilities & Shareholders Equity	$7.628B	$7.628B	$5.325B
YoY Change	43.26%	43.27%	10.43%

Cashflow Statement

Concept	2020 Q4	2020	2019 Q4
OPERATING ACTIVITIES
Net Income	$17.55M	$36.36M	$12.83M
YoY Change	36.84%	-32.52%	-2.66%
Depreciation, Depletion And Amortization	$1.700M	$5.800M	$1.700M
YoY Change	0.0%	7.41%	6.25%
Cash From Operating Activities	-$7.200M	$887.0K	$22.60M
YoY Change	-131.86%	-98.56%	64.96%
INVESTING ACTIVITIES
Capital Expenditures	-$4.000M	$7.198M	-$1.000M
YoY Change	300.0%	-35.46%	-23.08%
Acquisitions		$0.00
YoY Change
Other Investing Activities	-$354.0M	-$2.109B	$25.30M
YoY Change	-1499.21%	653.04%	-114.13%
Cash From Investing Activities	-$357.9M	-$2.116B	$24.20M
YoY Change	-1578.93%	626.59%	-113.42%
FINANCING ACTIVITIES
Cash Dividend Paid		$8.854M
YoY Change		51.01%
Common Stock Issuance & Retirement, Net		$723.0K
YoY Change		-92.81%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	520.4M	$2.201B	-64.00M
YoY Change	-913.13%	444.05%	-144.82%
NET CHANGE
Cash From Operating Activities	-7.200M	$887.0K	22.60M
Cash From Investing Activities	-357.9M	-$2.116B	24.20M
Cash From Financing Activities	520.4M	$2.201B	-64.00M
Net Change In Cash	155.3M	$85.70M	-17.20M
YoY Change	-1002.91%	-50.99%	-27.73%
FREE CASH FLOW
Cash From Operating Activities	-$7.200M	$887.0K	$22.60M
Capital Expenditures	-$4.000M	$7.198M	-$1.000M
Free Cash Flow	-$3.200M	-$6.311M	$23.60M
YoY Change	-113.56%	-112.52%	57.33%

Facts In Submission

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CY2020	us-gaap	Labor And Related Expense LaborAndRelatedExpense	91105000	USD
CY2019	us-gaap	Labor And Related Expense LaborAndRelatedExpense	88974000	USD
CY2018	us-gaap	Labor And Related Expense LaborAndRelatedExpense	80487000	USD
CY2020	obnk	Occupancy Netand Equipment Expense OccupancyNetandEquipmentExpense	17022000	USD
CY2019	obnk	Occupancy Netand Equipment Expense OccupancyNetandEquipmentExpense	16759000	USD
CY2018	obnk	Occupancy Netand Equipment Expense OccupancyNetandEquipmentExpense	15445000	USD
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	8321000	USD
CY2019	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	6961000	USD
CY2019	us-gaap	Loan Processing Fee LoanProcessingFee	4174000	USD
CY2018	us-gaap	Loan Processing Fee LoanProcessingFee	3039000	USD
CY2020	obnk	Officeand Operations Expense OfficeandOperationsExpense	5624000	USD
CY2018	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	6182000	USD
CY2020	obnk	Electronic Banking Expense ElectronicBankingExpense	3686000	USD
CY2019	obnk	Electronic Banking Expense ElectronicBankingExpense	3441000	USD
CY2018	obnk	Electronic Banking Expense ElectronicBankingExpense	2883000	USD
CY2020	us-gaap	Communication Communication	1767000	USD
CY2019	us-gaap	Communication Communication	2098000	USD
CY2018	us-gaap	Communication Communication	2028000	USD
CY2020	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	3710000	USD
CY2019	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	3808000	USD
CY2018	us-gaap	Marketing And Advertising Expense MarketingAndAdvertisingExpense	4275000	USD
CY2020	us-gaap	Professional Fees ProfessionalFees	3975000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	3577000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	3269000	USD
CY2020	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	3826000	USD
CY2019	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	1694000	USD
CY2018	us-gaap	Federal Deposit Insurance Corporation Premium Expense FederalDepositInsuranceCorporationPremiumExpense	2457000	USD
CY2020	us-gaap	Loan Processing Fee LoanProcessingFee	6316000	USD
CY2019	obnk	Officeand Operations Expense OfficeandOperationsExpense	6674000	USD
CY2018	obnk	Officeand Operations Expense OfficeandOperationsExpense	5881000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1060000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1321000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	961000	USD
CY2020	obnk	Franchise Tax Expense FranchiseTaxExpense	2186000	USD
CY2019	obnk	Franchise Tax Expense FranchiseTaxExpense	2160000	USD
CY2018	obnk	Franchise Tax Expense FranchiseTaxExpense	1485000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	3337000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	2433000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	2844000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	151935000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	144074000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	131236000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	44353000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	66548000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	62442000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7996000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12666000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10837000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	36357000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	53882000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	51605000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	1923000	USD
CY2020	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	0	USD
CY2019	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	0	USD
CY2018	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	1029000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	36357000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	53882000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	48653000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.56
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.56
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.30
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.21
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.55
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.28
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.20
CY2020	us-gaap	Net Income Loss NetIncomeLoss	36357000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	53882000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	51605000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	25646000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	11439000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-5260000	USD
CY2020	obnk	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Amortization Of Unrealized Losses On Available For Sale Securities Transferred To Held To Maturity Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForAmortizationOfUnrealizedLossesOnAvailableForSaleSecuritiesTransferredToHeldToMaturityBeforeTax	-10000	USD
CY2019	obnk	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Amortization Of Unrealized Losses On Available For Sale Securities Transferred To Held To Maturity Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForAmortizationOfUnrealizedLossesOnAvailableForSaleSecuritiesTransferredToHeldToMaturityBeforeTax	-10000	USD
CY2018	obnk	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Amortization Of Unrealized Losses On Available For Sale Securities Transferred To Held To Maturity Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForAmortizationOfUnrealizedLossesOnAvailableForSaleSecuritiesTransferredToHeldToMaturityBeforeTax	-10000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	580000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	20000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-8000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	25056000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	11409000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-5262000	USD
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	5262000	USD
CY2019	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	2396000	USD
CY2018	us-gaap	Other Comprehensive Income Availableforsale Securities Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent	-1105000	USD
CY2020	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	19794000	USD
CY2019	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	9013000	USD
CY2018	us-gaap	Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent	-4157000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-739000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	-216000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax	104000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	-134000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	37000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax	-7000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent	-605000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent	-253000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTaxParent	111000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	-127000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	-53000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTaxParent	23000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-478000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	88000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	19316000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	8813000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-4069000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	55673000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	62695000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	47536000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	420351000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	51605000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-4069000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	19316000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1998000	USD
CY2018	obnk	Employee Stock Ownership Plan Esop Terminationof Put Option EmployeeStockOwnershipPlanESOPTerminationofPutOption	34991000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	94676000	USD
CY2018	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	2706000	USD
CY2018	us-gaap	Stock Redeemed Or Called During Period Value StockRedeemedOrCalledDuringPeriodValue	48260000	USD
CY2018	us-gaap	Stock Issued During Period Value Conversion Of Convertible Securities StockIssuedDuringPeriodValueConversionOfConvertibleSecurities	0	USD
CY2018	obnk	Adjustments To Additional Paid In Capital Stock Issued Income Tax Benefit From Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIncomeTaxBenefitFromIssuanceCosts	641000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.13
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	2937000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	549779000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	53882000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	8813000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2413000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.25
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	5887000	USD
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	10059000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	599262000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	36357000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2568000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.3775
CY2020	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	570349000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	8870000	USD
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	723000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	647150000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	36357000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	53882000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	51605000	USD
CY2020	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	59900000	USD
CY2019	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	9568000	USD
CY2018	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	1014000	USD
CY2020	obnk	Depreciationand Amortization Excluding Amortizationof Investment Premiumsand Discountsand Qualified Affordable Housing Projects Investments DepreciationandAmortizationExcludingAmortizationofInvestmentPremiumsandDiscountsandQualifiedAffordableHousingProjectsInvestments	6880000	USD
CY2019	obnk	Depreciationand Amortization Excluding Amortizationof Investment Premiumsand Discountsand Qualified Affordable Housing Projects Investments DepreciationandAmortizationExcludingAmortizationofInvestmentPremiumsandDiscountsandQualifiedAffordableHousingProjectsInvestments	6706000	USD
CY2018	obnk	Depreciationand Amortization Excluding Amortizationof Investment Premiumsand Discountsand Qualified Affordable Housing Projects Investments DepreciationandAmortizationExcludingAmortizationofInvestmentPremiumsandDiscountsandQualifiedAffordableHousingProjectsInvestments	5869000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-4581000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-975000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-1138000	USD
CY2020	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	1442000	USD
CY2019	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	1608000	USD
CY2018	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	1899000	USD
CY2020	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	580000	USD
CY2019	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	20000	USD
CY2018	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	-8000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-11884000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-2596000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	5637000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	2320000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	2247000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	1462000	USD
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	659188000	USD
CY2019	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	353090000	USD
CY2018	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	300093000	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	334958000	USD
CY2018	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	309153000	USD
CY2020	obnk	Gainon Saleof Loans Including Servicing Rights Origination GainonSaleofLoansIncludingServicingRightsOrigination	19190000	USD
CY2019	obnk	Gainon Saleof Loans Including Servicing Rights Origination GainonSaleofLoansIncludingServicingRightsOrigination	6943000	USD
CY2018	obnk	Gainon Saleof Loans Including Servicing Rights Origination GainonSaleofLoansIncludingServicingRightsOrigination	6403000	USD
CY2020	us-gaap	Mortgage Servicing Rights Msr Impairment Recovery MortgageServicingRightsMSRImpairmentRecovery	12746000	USD
CY2019	us-gaap	Mortgage Servicing Rights Msr Impairment Recovery MortgageServicingRightsMSRImpairmentRecovery	7012000	USD
CY2018	us-gaap	Mortgage Servicing Rights Msr Impairment Recovery MortgageServicingRightsMSRImpairmentRecovery	963000	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-72000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-139000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-75000	USD
CY2020	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	917000	USD
CY2019	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	755000	USD
CY2018	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	713000	USD
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	0	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	367000	USD
CY2018	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	1977000	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-1141000	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-194000	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	-95000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	3142000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-8035000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-8094000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	887000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	61553000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	77826000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	6596000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	700319000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	94544000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	477548000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	279152000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	151932000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	154473000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	64702000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	27766000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	20877000	USD
CY2020	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	10000000	USD
CY2019	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	10000000	USD
CY2018	us-gaap	Payments To Acquire Held To Maturity Securities PaymentsToAcquireHeldToMaturitySecurities	0	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	415000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	541000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1018000	USD
CY2020	obnk	Proceedsfrom Maturities Repaymentsand Callsof Equity Securities Fvni ProceedsfromMaturitiesRepaymentsandCallsofEquitySecuritiesFVNI	452000	USD
CY2019	obnk	Proceedsfrom Maturities Repaymentsand Callsof Equity Securities Fvni ProceedsfromMaturitiesRepaymentsandCallsofEquitySecuritiesFVNI	434000	USD
CY2018	obnk	Proceedsfrom Maturities Repaymentsand Callsof Equity Securities Fvni ProceedsfromMaturitiesRepaymentsandCallsofEquitySecuritiesFVNI	414000	USD
CY2020	obnk	Payments For Proceeds From Other Investments PaymentsForProceedsFromOtherInvestments	22401000	USD
CY2019	obnk	Payments For Proceeds From Other Investments PaymentsForProceedsFromOtherInvestments	-3386000	USD
CY2018	obnk	Payments For Proceeds From Other Investments PaymentsForProceedsFromOtherInvestments	17026000	USD
CY2020	obnk	Paymentsfor Warehouse Purchase Program Loan Heldfor Investment PaymentsforWarehousePurchaseProgramLoanHeldforInvestment	13665295000	USD
CY2019	obnk	Paymentsfor Warehouse Purchase Program Loan Heldfor Investment PaymentsforWarehousePurchaseProgramLoanHeldforInvestment	4306171000	USD
CY2018	obnk	Paymentsfor Warehouse Purchase Program Loan Heldfor Investment PaymentsforWarehousePurchaseProgramLoanHeldforInvestment	4495650000	USD
CY2020	obnk	Proceedsfrom Warehouse Purchase Program Loan Heldfor Investment ProceedsfromWarehousePurchaseProgramLoanHeldforInvestment	12855955000	USD
CY2019	obnk	Proceedsfrom Warehouse Purchase Program Loan Heldfor Investment ProceedsfromWarehousePurchaseProgramLoanHeldforInvestment	4239381000	USD
CY2018	obnk	Proceedsfrom Warehouse Purchase Program Loan Heldfor Investment ProceedsfromWarehousePurchaseProgramLoanHeldforInvestment	4542822000	USD
CY2020	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	788719000	USD
CY2019	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	290278000	USD
CY2018	us-gaap	Payments To Acquire Finance Receivables PaymentsToAcquireFinanceReceivables	601153000	USD
CY2020	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2019	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	4500000	USD
CY2018	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	4000000	USD
CY2020	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	818000	USD
CY2019	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	503000	USD
CY2018	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	456000	USD
CY2020	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	525000	USD
CY2019	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	1521000	USD
CY2018	us-gaap	Payments To Acquire Limited Partnership Interests PaymentsToAcquireLimitedPartnershipInterests	2838000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7198000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11152000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	5482000	USD
CY2020	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2019	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	27000	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	111000	USD
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	4451000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	470000	USD
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	516000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2115732000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-291185000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-764927000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	1522703000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	445474000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	271124000	USD
CY2020	obnk	Proceedsfrom Fhl Bank Borrowings Long Term Advances Financing Activities ProceedsfromFHLBankBorrowingsLongTermAdvancesFinancingActivities	0	USD
CY2019	obnk	Proceedsfrom Fhl Bank Borrowings Long Term Advances Financing Activities ProceedsfromFHLBankBorrowingsLongTermAdvancesFinancingActivities	100000000	USD
CY2018	obnk	Proceedsfrom Fhl Bank Borrowings Long Term Advances Financing Activities ProceedsfromFHLBankBorrowingsLongTermAdvancesFinancingActivities	250000000	USD
CY2020	obnk	Payments Of Fhl Bank Borrowings Long Term Advances Financing Activities PaymentsOfFHLBankBorrowingsLongTermAdvancesFinancingActivities	1898000	USD
CY2019	obnk	Payments Of Fhl Bank Borrowings Long Term Advances Financing Activities PaymentsOfFHLBankBorrowingsLongTermAdvancesFinancingActivities	101649000	USD
CY2018	obnk	Payments Of Fhl Bank Borrowings Long Term Advances Financing Activities PaymentsOfFHLBankBorrowingsLongTermAdvancesFinancingActivities	51342000	USD
CY2020	obnk	Proceeds From Federal Reserve Bank Paycheck Protection Program Liquidity Facility ProceedsFromFederalReserveBankPaycheckProtectionProgramLiquidityFacility	319257000	USD
CY2019	obnk	Proceeds From Federal Reserve Bank Paycheck Protection Program Liquidity Facility ProceedsFromFederalReserveBankPaycheckProtectionProgramLiquidityFacility	0	USD
CY2018	obnk	Proceeds From Federal Reserve Bank Paycheck Protection Program Liquidity Facility ProceedsFromFederalReserveBankPaycheckProtectionProgramLiquidityFacility	0	USD
CY2020	obnk	Payments Of Federal Reserve Bank Paycheck Protection Program Liquidity Facility PaymentsOfFederalReserveBankPaycheckProtectionProgramLiquidityFacility	319257000	USD
CY2019	obnk	Payments Of Federal Reserve Bank Paycheck Protection Program Liquidity Facility PaymentsOfFederalReserveBankPaycheckProtectionProgramLiquidityFacility	0	USD
CY2018	obnk	Payments Of Federal Reserve Bank Paycheck Protection Program Liquidity Facility PaymentsOfFederalReserveBankPaycheckProtectionProgramLiquidityFacility	0	USD
CY2020	obnk	Proceedsfrom Fhl Bank Borrowings Short Term Advances Financing Activities ProceedsfromFHLBankBorrowingsShortTermAdvancesFinancingActivities	2107000000	USD
CY2019	obnk	Proceedsfrom Fhl Bank Borrowings Short Term Advances Financing Activities ProceedsfromFHLBankBorrowingsShortTermAdvancesFinancingActivities	2815000000	USD
CY2018	obnk	Proceedsfrom Fhl Bank Borrowings Short Term Advances Financing Activities ProceedsfromFHLBankBorrowingsShortTermAdvancesFinancingActivities	667065000	USD
CY2020	obnk	Payments Of Fhl Bank Borrowings Short Term Advances Financing Activities PaymentsOfFHLBankBorrowingsShortTermAdvancesFinancingActivities	1557000000	USD
CY2019	obnk	Payments Of Fhl Bank Borrowings Short Term Advances Financing Activities PaymentsOfFHLBankBorrowingsShortTermAdvancesFinancingActivities	2815000000	USD
CY2018	obnk	Payments Of Fhl Bank Borrowings Short Term Advances Financing Activities PaymentsOfFHLBankBorrowingsShortTermAdvancesFinancingActivities	567065000	USD
CY2020	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	0	USD
CY2019	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	0	USD
CY2018	us-gaap	Proceeds From Repayments Of Other Debt ProceedsFromRepaymentsOfOtherDebt	1164000	USD
CY2020	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	147374000	USD
CY2019	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Subordinated Long Term Debt ProceedsFromIssuanceOfSubordinatedLongTermDebt	0	USD
CY2020	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-8309000	USD
CY2019	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	-23597000	USD
CY2018	us-gaap	Increase Decrease In Federal Funds Purchased And Securities Sold Under Agreements To Repurchase Net IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet	4135000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	8854000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	5863000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	5941000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	0	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	25000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	248000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	166000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	559000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	95178000	USD
CY2020	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2019	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2018	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	48260000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	723000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	10059000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	2200541000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	404472000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	616592000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	85696000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	174840000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-70509000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	291518000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	116678000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	187187000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	377214000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	291518000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	116678000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	36432000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	53227000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	34390000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	24974000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	10023000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	675000	USD
CY2020	obnk	Unsettled Liability For Investment Purchases Recorded At Trade Date UnsettledLiabilityForInvestmentPurchasesRecordedAtTradeDate	1514000	USD
CY2019	obnk	Unsettled Liability For Investment Purchases Recorded At Trade Date UnsettledLiabilityForInvestmentPurchasesRecordedAtTradeDate	2659000	USD
CY2018	obnk	Unsettled Liability For Investment Purchases Recorded At Trade Date UnsettledLiabilityForInvestmentPurchasesRecordedAtTradeDate	0	USD
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	2446000	USD
CY2019	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	1577000	USD
CY2018	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	1057000	USD
CY2020	us-gaap	Conversion Of Stock Amount Converted1 ConversionOfStockAmountConverted1	0	USD
CY2019	us-gaap	Conversion Of Stock Amount Converted1 ConversionOfStockAmountConverted1	0	USD
CY2018	us-gaap	Conversion Of Stock Amount Converted1 ConversionOfStockAmountConverted1	16998000	USD
CY2020	us-gaap	Stock Issued1 StockIssued1	0	USD
CY2019	us-gaap	Stock Issued1 StockIssued1	0	USD
CY2018	us-gaap	Stock Issued1 StockIssued1	2706000	USD
CY2020Q4	us-gaap	Number Of Stores NumberOfStores	44	center
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2019Q4	us-gaap	Other Real Estate OtherRealEstate	4700000	USD
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Reclassifications</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">. Certain amounts previously reported have been reclassified to conform to the current presentation. Such reclassifications had no effect on prior year net income or stockholders' equity.</span>
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions based on available information that affect the amounts reported in the financial statements and disclosures provided, including the accompanying notes, and actual results could differ. Material estimates that are particularly susceptible to change include the allowance for credit losses for loans and available for sale securities; fair value measurements of assets and liabilities; and income taxes. Estimates and assumptions are reviewed periodically and the effects of revisions are reflected in the Company's consolidated financial statements in the period they are deemed necessary. While management uses its best judgment, actual results could differ from those estimates.</span>
CY2019Q4	us-gaap	Federal Home Loan Bank Stock And Federal Reserve Bank Stock FederalHomeLoanBankStockAndFederalReserveBankStock	12100000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock And Federal Reserve Bank Stock FederalHomeLoanBankStockAndFederalReserveBankStock	12100000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts	<div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Allowance for Credit Losses</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">. The allowance for loan credit losses represents the estimated losses for financial assets accounted for on an amortized cost basis. Expected losses are calculated using relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. The Company evaluates loans held for investment ("LHFI") on a pool basis with pools of loans characterized by loan type, collateral, industry, internal credit risk rating and Fair Isaac Corporation ("FICO") score. The Company applied a probability of default, loss given default loss methodology to the loan pools at January 1 and December 31, 2020. Historical loss rates for each pool are calculated based on charge-off and recovery data beginning with the second quarter of 2012. These loss rates are adjusted for differences between current period conditions, including the ongoing effects of COVID-19 on the U.S. economy, and the conditions existing during the historical loss period. Historical losses are additionally adjusted for the effects of certain economic variables forecast over a one-year period. Subsequent to the forecast effects, historical loss rates are used to estimate losses over the estimated remaining lives of the loans. The estimated remaining lives consist of the contractual lives, adjusted for estimated prepayments. Loans that exhibit characteristics different from their pool characteristics are evaluated on an individual basis. Certain of these loans are considered to be collateral dependent with the borrower experiencing financial difficulty. For these loans, the fair value of collateral practical expedient is elected whereby the allowance is calculated as the amount by which the amortized cost exceeds the fair value of collateral, less costs to sell (if applicable). Those individual loans that are not collateral dependent are evaluated based on a discounted cash flow methodology. This evaluation is inherently subjective as it requires estimates that are susceptible to significant revision as more information becomes available. Loans are charged off against the allowance for credit losses when management believes the loss is confirmed. Subsequent recoveries, if any, are credited to the allowance.</span></div><div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Prior to the adoption of ASU 2016-13, the allowance for credit losses on loans was established through a provision for loan losses charged to expense, which represented management’s best estimate of inherent losses that had been incurred within the existing portfolio of loans. The allowance for credit losses on loans included allowance allocations calculated in accordance with ASC Topic 310, “Receivables” and allowance allocations calculated in accordance with ASC Topic 450, “Contingencies.” </span></div><div style="margin-bottom:9pt;text-align:justify;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Delinquency statistics are updated at least monthly and are the most meaningful indicator of the credit quality of one-to-four single family residential, home equity loans and lines of credit and other consumer loans. Internal risk ratings are considered the most meaningful indicator of credit quality for commercial and industrial, construction, and commercial real estate loans. Internal risk ratings are a key factor in identifying loans that are individually evaluated for impairment and impact management's estimates of loss factors used in determining the amount of the allowance for credit losses. Internal risk ratings are updated on a regular basis.</span></div><div style="margin-bottom:9pt;text-align:justify;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Prior to the adoption of ASC 326 on January 1, 2020, loans were reported as impaired when, based on then current information and events, it was probable that the Company would be unable to collect all amounts due in accordance with the original contractual terms of the loan agreement, including scheduled principal and interest payments. Impairment was evaluated in total for smaller-balance loans of a similar nature and on an individual loan basis for other loans. If a loan was impaired, a specific valuation allowance was allocated, if necessary, so that the loan was reported net, at the present value of estimated future cash flows using the loan’s existing rate or at the fair value of collateral if repayment was expected solely from the collateral. Interest payments on impaired loans were typically applied to principal unless collectibility of the principal amount was reasonably assured, in which case interest was recognized on a cash basis. Impaired loans, or portions thereof, were charged off when deemed uncollectible.</span></div><div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Troubled debt restructurings ("TDRs") are loans for which the contractual terms on the loan have been modified and both of the following conditions exist: (1) the borrower is experiencing financial difficulty and (2) the restructuring constitutes a concession. Concessions could include a reduction in the interest rate on the loan, payment extensions, forgiveness of principal, forbearance or other actions intended to maximize collection. The Company assesses all loan modifications to determine whether they constitute a TDR.</span></div><div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Certain borrowers are currently unable to meet their contractual payment obligations because of the adverse effects of COVID-19. To help mitigate these effects, loan customers may apply for a deferral of payments, or portions thereof, for up to 90 days. The CARES Act and related guidance from the federal banking agencies provide financial institutions the option to temporarily suspend requirements under GAAP related to classification of certain loan modifications as TDRs to account for the current and anticipated effects of COVID-19. The CARES Act, as amended by the Consolidated Appropriations Act, 2021, specified that COVID-19 related loan modifications executed between March 1, 2020 and the earlier of (i) 60 days after the date of termination of the national emergency declared by the President and (ii) January 1, 2022, on loans that were current as of December 31, 2019 are not TDRs. Additionally, under guidance from the federal banking agencies, other short-term modifications made on a good faith in response to COVID-19 to borrowers that were current prior to any relief are not TDRs under ASC Subtopic 310-40, “Troubled Debt Restructuring by Creditors.” These modifications include short-term (e.g., up to six months) modifications such as payment deferrals, fee waivers, extensions of repayment terms, or delays in payment that are insignificant. At December 31, 2020, the Company had 49 loans totaling $97.7 million under COVID-19 related forbearance agreements.</span></div><div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The allowance for off-balance sheet exposures was determined using the same methodology that is applied to LHFI. Utilization rates are determined based on historical usage.</span></div><div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Credit losses related to available for sale debt securities are recorded through an allowance for credit losses. The amount of the allowance for credit losses is limited to the amount by which fair value is below amortized cost. Discounted cash flow analysis is required for determining credit losses for available for sale securities. In determining whether or not a credit loss exists, such factors as extent of the loss, adverse conditions related to the entity, industry or geographic region, security structure, ratings and changes by a rating agency and past performance are considered. The length of time a security has been in an unrealized loss position is not a factor in determining whether a credit loss exists.</span></div><div style="margin-bottom:9pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The allowance for credit losses for held-to-maturity securities is calculated using a probability of default, loss given default methodology. Credit losses are estimated over the lives of the securities using historical loss rates, adjusted for current conditions and reasonable and supportable forecasts. Third party data is used for the historical loss rates and probability of default statistics. Additionally, the Company uses a weighted average of three possible economic scenarios derived from third party data which is used to calculate the forecast effect. The forecast effect is applied over the estimated lives of the securities.</span></div>
CY2020Q4	obnk	Financing Receivable Coronavirus Aid Relief And Economic Securities Cares Act Number Of Loans In Forbearance FinancingReceivableCoronavirusAidReliefAndEconomicSecuritiesCARESActNumberOfLoansInForbearance	49	loan
CY2020Q4	obnk	Financing Receivable Coronavirus Aid Relief And Economic Securities Cares Act Forbearance FinancingReceivableCoronavirusAidReliefAndEconomicSecuritiesCARESActForbearance	97700000	USD
CY2020Q4	us-gaap	Other Real Estate OtherRealEstate	1600000	USD
CY2018	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	0	USD
CY2019	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	0	USD
CY2020	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	0	USD
CY2020Q4	us-gaap	Other Investments OtherInvestments	15700000	USD
CY2019Q4	us-gaap	Other Investments OtherInvestments	16000000.0	USD
CY2020Q4	obnk	Investment In Tax Credit Entities InvestmentInTaxCreditEntities	7600000	USD
CY2019Q4	obnk	Investment In Tax Credit Entities InvestmentInTaxCreditEntities	9000000.0	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37520000	USD
CY2019Q4	us-gaap	Off Balance Sheet Credit Loss Liability OffBalanceSheetCreditLossLiability	1810000	USD
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	36357000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	53882000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	51605000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	1923000	USD
CY2020	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	0	USD
CY2019	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	0	USD
CY2018	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	1029000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	36357000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	53882000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	48653000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23367221	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23367221	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23470746	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	21995990	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.56
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.56
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.30
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.21
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	36357000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	53882000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	48819000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23367221	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23367221	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	23470746	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	21995990	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	144731	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	203319	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	198439	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	23511952	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	23674065	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	22194429	shares
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.55
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.28
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.20
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	971595000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	33972000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	893000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1004674000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2020Q4	obnk	Debt Securities Available For Sale Net Of Allowance For Credit Loss DebtSecuritiesAvailableForSaleNetOfAllowanceForCreditLoss	1004674000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	493058000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	8628000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	616000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	501070000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
CY2019Q4	obnk	Debt Securities Available For Sale Net Of Allowance For Credit Loss DebtSecuritiesAvailableForSaleNetOfAllowanceForCreditLoss	501070000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	119581000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	888000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	568000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	5000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	120149000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	893000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	56446000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	304000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	39855000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	312000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	96301000	USD
CY2019Q4	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	64837000	USD
CY2020Q4	obnk	Financing Receivable Excluding Loans At Fair Value Before Allowancefor Credit Loss FinancingReceivableExcludingLoansAtFairValueBeforeAllowanceforCreditLoss	5707762000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	616000	USD
CY2020Q4	obnk	Securitiesin Unrealized Loss Positions Qualitative Disclosure Numberof Positions SecuritiesinUnrealizedLossPositionsQualitativeDisclosureNumberofPositions	44	loan
CY2019Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	0	USD
CY2020	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	-30000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	66000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Accrued Interest After Allowance For Credit Loss DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss	5400000	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Past Due DebtSecuritiesHeldToMaturityPastDue	0	USD
CY2020Q4	us-gaap	Debt Securities Held To Maturity Nonaccrual DebtSecuritiesHeldToMaturityNonaccrual	0	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	64702000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	27766000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	20877000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	774000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	161000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	381000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	194000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	141000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	389000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Next Rolling Twelve Months Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost	12999000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Next Rolling Twelve Months Fair Value HeldToMaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	13068000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis	3210000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Next Rolling Twelve Months Fair Value AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue	3237000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Two Through Five Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling Year Two Through Five Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	0	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis	47500000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Two Through Five Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue	51572000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost	25195000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling Year Six Through Ten Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	28137000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis	111383000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue	115206000	USD
CY2020Q4	us-gaap	Heldtomaturity Securities Debt Maturities Rolling After Ten Years Amortized Cost HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Rolling After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesRollingAfterTenYearsFairValue	0	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis	323630000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Rolling After Year Ten Fair Value AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue	338957000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	38194000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	41205000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	971595000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	1004674000	USD
CY2020Q4	us-gaap	Loans Receivable Held For Sale Amount LoansReceivableHeldForSaleAmount	191512000	USD
CY2019Q4	obnk	Financing Receivable Excluding Loans At Fair Value Before Allowancefor Credit Loss FinancingReceivableExcludingLoansAtFairValueBeforeAllowanceforCreditLoss	4125525000	USD
CY2020Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	17011000	USD
CY2019Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	17670000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	5724773000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	4143195000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	86670000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37520000	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	5638103000	USD
CY2019Q4	us-gaap	Notes Receivable Net NotesReceivableNet	4105675000	USD
CY2020Q4	us-gaap	Financing Receivable Deferred Income FinancingReceivableDeferredIncome	13700000	USD
CY2019Q4	us-gaap	Financing Receivable Deferred Income FinancingReceivableDeferredIncome	3600000	USD
CY2020Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	17000000.0	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	4143195000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	25763000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	5699010000	USD
CY2020Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	5724773000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2020Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	17000000.0	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	29980000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	4113215000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	4143195000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2020Q4	obnk	Financing Receivable Accrued Interest FinancingReceivableAccruedInterest	20300000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37520000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	12394000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1268000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	59028000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	86670000	USD
CY2020	obnk	Credit Loss Expense Reversal CreditLossExpenseReversal	59900000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	59000000.0	USD
CY2020	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	902000	USD
CY2020	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	-30000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	34203000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	10131000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	4241000	USD
CY2019	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	9207000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37520000	USD
CY2019	obnk	Credit Loss Expense Reversal CreditLossExpenseReversal	9600000	USD
CY2019	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	9200000	USD
CY2019	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	361000	USD
CY2017Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37083000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	7124000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	2663000	USD
CY2018	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	1581000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	34203000	USD
CY2018	obnk	Credit Loss Expense Reversal CreditLossExpenseReversal	1000000.0	USD
CY2018	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	1600000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1100000	USD
CY2018	us-gaap	Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal	-567000	USD
CY2020	obnk	Financing Receivable Coronavirus Pandemic Credit Loss Changes Expense Reversal FinancingReceivableCoronavirusPandemicCreditLossChangesExpenseReversal	39800000	USD
CY2020	obnk	Financing Receivable Coronavirus Pandemic Credit Loss Related To Factor Changes Expense Reversal FinancingReceivableCoronavirusPandemicCreditLossRelatedToFactorChangesExpenseReversal	27500000	USD
CY2020Q4	obnk	Financing Receivable Coronavirus Pandemic Allowance For Credit Losses Individually Evaluated For Impairment FinancingReceivableCoronavirusPandemicAllowanceForCreditLossesIndividuallyEvaluatedForImpairment	8100000	USD
CY2020	obnk	Financing Receivable Number Of Write Offs FinancingReceivableNumberOfWriteOffs	4	loan
CY2020Q4	obnk	Financing Receivable Excluding Loans At Fair Value Before Allowancefor Credit Loss FinancingReceivableExcludingLoansAtFairValueBeforeAllowanceforCreditLoss	5707762000	USD
CY2020Q4	us-gaap	Loans Receivable Fair Value Disclosure LoansReceivableFairValueDisclosure	17000000.0	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	86670000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	199000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	37321000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	32474000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	4093051000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	44293000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	30423000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	2051000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	32474000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	199000	USD
CY2020Q4	us-gaap	Financing Receivable Nonaccrual No Allowance FinancingReceivableNonaccrualNoAllowance	4890000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	26149000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	31146000	USD
CY2020Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	681000	USD
CY2019Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	927000	USD
CY2020Q4	obnk	Financing Receivable Coronavirus Aid Relief And Economic Securities Cares Act Number Of Loans In Forbearance FinancingReceivableCoronavirusAidReliefAndEconomicSecuritiesCARESActNumberOfLoansInForbearance	49	loan
CY2020Q4	obnk	Financing Receivable Coronavirus Aid Relief And Economic Securities Cares Act Forbearance FinancingReceivableCoronavirusAidReliefAndEconomicSecuritiesCARESActForbearance	97700000	USD
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	8985000	USD
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	8452000	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	loan
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	2	loan
CY2020Q4	us-gaap	Goodwill Goodwill	26741000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	26741000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	35761000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	5281000	USD
CY2020Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	30480000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	26741000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	26741000	USD
CY2018	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	loan
CY2020Q4	obnk	Fair Value Option Aggregate Fair Value FairValueOptionAggregateFairValue	164591000	USD
CY2020Q4	obnk	Fair Value Option Aggregate Unpaid Principal Balance FairValueOptionAggregateUnpaidPrincipalBalance	157333000	USD
CY2020Q4	us-gaap	Fair Value Option Aggregate Differences Loans And Long Term Receivables FairValueOptionAggregateDifferencesLoansAndLongTermReceivables	7258000	USD
CY2020Q4	us-gaap	Fair Value Option Loans Held As Assets Aggregate Amount In Nonaccrual Status FairValueOptionLoansHeldAsAssetsAggregateAmountInNonaccrualStatus	0	USD
CY2019Q4	obnk	Fair Value Option Aggregate Fair Value FairValueOptionAggregateFairValue	66160000	USD
CY2019Q4	obnk	Fair Value Option Aggregate Unpaid Principal Balance FairValueOptionAggregateUnpaidPrincipalBalance	64473000	USD
CY2019Q4	us-gaap	Fair Value Option Aggregate Differences Loans And Long Term Receivables FairValueOptionAggregateDifferencesLoansAndLongTermReceivables	1687000	USD
CY2019Q4	us-gaap	Fair Value Option Loans Held As Assets Aggregate Amount In Nonaccrual Status FairValueOptionLoansHeldAsAssetsAggregateAmountInNonaccrualStatus	0	USD
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	62600000	USD
CY2019Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	39800000	USD
CY2020Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Impairment Loss Cumulative Amount EquitySecuritiesWithoutReadilyDeterminableFairValueImpairmentLossCumulativeAmount	0	USD
CY2020Q4	obnk	Liabilityto Repurchase Nonconforming Gnma Loans LiabilitytoRepurchaseNonconformingGNMALoans	55500000	USD
CY2019Q4	obnk	Liabilityto Repurchase Nonconforming Gnma Loans LiabilitytoRepurchaseNonconformingGNMALoans	27900000	USD
CY2020Q4	us-gaap	Deposits Deposits	5751315000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	131564000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	127269000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	49801000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	46812000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	81763000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	80457000	USD
CY2020	us-gaap	Depreciation Depreciation	5800000	USD
CY2019	us-gaap	Depreciation Depreciation	5400000	USD
CY2018	us-gaap	Depreciation Depreciation	4900000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	21667000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	24013000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	23445000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	25810000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	3148000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	248000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y2M19D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y6M29D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0344
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0349
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	4680000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	4716000	USD
CY2020	obnk	Lease Other Cost LeaseOtherCost	265000	USD
CY2019	obnk	Lease Other Cost LeaseOtherCost	245000	USD
CY2020	us-gaap	Lease Cost LeaseCost	4945000	USD
CY2019	us-gaap	Lease Cost LeaseCost	4961000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	1338000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	1256000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	4400000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	4330000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4064000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	3638000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	2584000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2040000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	11165000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	27821000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	4376000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	23445000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	4791000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	4796000	USD
CY2019Q4	obnk	Intangible Assets Gross Including Goodwill IntangibleAssetsGrossIncludingGoodwill	35761000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	4221000	USD
CY2019Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	31540000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1300000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	961000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	844000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	689000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	582000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	488000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	393000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	743000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	3739000	USD
CY2020	obnk	Mortgage Banking Revenue Origination MortgageBankingRevenueOrigination	1880000	USD
CY2019	obnk	Mortgage Banking Revenue Origination MortgageBankingRevenueOrigination	1000000	USD
CY2018	obnk	Mortgage Banking Revenue Origination MortgageBankingRevenueOrigination	854000	USD
CY2020	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	19190000	USD
CY2019	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	6943000	USD
CY2018	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	6403000	USD
CY2020	obnk	Servicing Fees Net1 ServicingFeesNet1	6116000	USD
CY2019	obnk	Servicing Fees Net1 ServicingFeesNet1	6547000	USD
CY2018	obnk	Servicing Fees Net1 ServicingFeesNet1	7081000	USD
CY2020	obnk	Gross Mortgage Revenue GrossMortgageRevenue	27186000	USD
CY2019	obnk	Gross Mortgage Revenue GrossMortgageRevenue	14490000	USD
CY2018	obnk	Gross Mortgage Revenue GrossMortgageRevenue	14338000	USD
CY2020	obnk	Mortgage Servicing Rightand Hedge Fair Value Adjustment MortgageServicingRightandHedgeFairValueAdjustment	7351000	USD
CY2019	obnk	Mortgage Servicing Rightand Hedge Fair Value Adjustment MortgageServicingRightandHedgeFairValueAdjustment	979000	USD
CY2018	obnk	Mortgage Servicing Rightand Hedge Fair Value Adjustment MortgageServicingRightandHedgeFairValueAdjustment	-725000	USD
CY2020	obnk	Mortgage Servicing Rights Valuation Adjustment Net Of Amortization MortgageServicingRightsValuationAdjustmentNetOfAmortization	-12746000	USD
CY2019	obnk	Mortgage Servicing Rights Valuation Adjustment Net Of Amortization MortgageServicingRightsValuationAdjustmentNetOfAmortization	-7012000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	14184000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	14094000	USD
CY2018	obnk	Mortgage Servicing Rights Valuation Adjustment Net Of Amortization MortgageServicingRightsValuationAdjustmentNetOfAmortization	-963000	USD
CY2020	obnk	Mortgage Servicing Right Hedge Impact MortgageServicingRightHedgeImpact	7812000	USD
CY2019	obnk	Mortgage Servicing Right Hedge Impact MortgageServicingRightHedgeImpact	3852000	USD
CY2018	obnk	Mortgage Servicing Right Hedge Impact MortgageServicingRightHedgeImpact	-3030000	USD
CY2020	obnk	Mortgage Banking Revenue MortgageBankingRevenue	29603000	USD
CY2019	obnk	Mortgage Banking Revenue MortgageBankingRevenue	12309000	USD
CY2018	obnk	Mortgage Banking Revenue MortgageBankingRevenue	9620000	USD
CY2019Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	20697000	USD
CY2018Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	25114000	USD
CY2017Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	24182000	USD
CY2020	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	5709000	USD
CY2019	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	2595000	USD
CY2018	us-gaap	Servicing Asset At Fair Value Additions ServicingAssetAtFairValueAdditions	1895000	USD
CY2020	us-gaap	Servicing Asset At Fair Value Changes In Fair Value Resulting From Changes In Valuation Inputs Or Changes In Assumptions ServicingAssetAtFairValueChangesInFairValueResultingFromChangesInValuationInputsOrChangesInAssumptions	-12746000	USD
CY2019	us-gaap	Servicing Asset At Fair Value Changes In Fair Value Resulting From Changes In Valuation Inputs Or Changes In Assumptions ServicingAssetAtFairValueChangesInFairValueResultingFromChangesInValuationInputsOrChangesInAssumptions	-7012000	USD
CY2018	us-gaap	Servicing Asset At Fair Value Changes In Fair Value Resulting From Changes In Valuation Inputs Or Changes In Assumptions ServicingAssetAtFairValueChangesInFairValueResultingFromChangesInValuationInputsOrChangesInAssumptions	-963000	USD
CY2020Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	13660000	USD
CY2019Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	20697000	USD
CY2018Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	25114000	USD
CY2020	obnk	Servicing Fee Income Rate ServicingFeeIncomeRate	0.0028
CY2020	obnk	Mortgage Loan Servicing Putback Expenses MortgageLoanServicingPutbackExpenses	82000	USD
CY2019	obnk	Mortgage Loan Servicing Putback Expenses MortgageLoanServicingPutbackExpenses	33000	USD
CY2020Q4	obnk	Mortgage Loan Servicing Putback Expenses Reserve MortgageLoanServicingPutbackExpensesReserve	311000	USD
CY2019Q4	obnk	Mortgage Loan Servicing Putback Expenses Reserve MortgageLoanServicingPutbackExpensesReserve	229000	USD
CY2020Q4	obnk	Liabilityto Repurchase Nonconforming Gnma Loans LiabilitytoRepurchaseNonconformingGNMALoans	55500000	USD
CY2019Q4	obnk	Liabilityto Repurchase Nonconforming Gnma Loans LiabilitytoRepurchaseNonconformingGNMALoans	27900000	USD
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	1607564000	USD
CY2019Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	1077706000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Demand InterestBearingDomesticDepositDemand	1052639000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Demand InterestBearingDomesticDepositDemand	776037000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	1789914000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	1277053000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	431180000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	152556000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	205252000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	154450000	USD
CY2020Q4	obnk	Time Deposits Excluding Time Deposits Brokered TimeDepositsExcludingTimeDepositsBrokered	664766000	USD
CY2019Q4	obnk	Time Deposits Excluding Time Deposits Brokered TimeDepositsExcludingTimeDepositsBrokered	790810000	USD
CY2020Q4	us-gaap	Deposits Deposits	5751315000	USD
CY2019Q4	us-gaap	Deposits Deposits	4228612000	USD
CY2020Q4	obnk	Deposits Municipal DepositsMunicipal	689300000	USD
CY2019Q4	obnk	Deposits Municipal DepositsMunicipal	423800000	USD
CY2020	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.06
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	497516000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	271300000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	319100000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	103156000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	31272000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	25025000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	7797000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	664766000	USD
CY2020Q4	us-gaap	Bank Overdrafts BankOverdrafts	462000	USD
CY2019Q4	us-gaap	Bank Overdrafts BankOverdrafts	1100000	USD
CY2020Q4	obnk	Federal Home Loan Bank Advances And Securities Sold Under Agreements To Repurchase FederalHomeLoanBankAdvancesAndSecuritiesSoldUnderAgreementsToRepurchase	984608000	USD
CY2019Q4	obnk	Federal Home Loan Bank Advances And Securities Sold Under Agreements To Repurchase FederalHomeLoanBankAdvancesAndSecuritiesSoldUnderAgreementsToRepurchase	417190000	USD
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P5Y9M21D
CY2020	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.06
CY2020Q4	obnk	Debt Instrument Number Of Grantor Trusts DebtInstrumentNumberOfGrantorTrusts	2	trust
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	1030766000	USD
CY2019Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	762012000	USD
CY2020Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	1380000	USD
CY2019Q4	us-gaap	Derivative Assets Liabilities At Fair Value Net DerivativeAssetsLiabilitiesAtFairValueNet	-3000	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	6932000	USD
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	30000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	8.25
CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	22200000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	15300000	USD
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P20Y
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	0	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	254000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	10.55
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	319500	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	10.65
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y25D
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	4840000	USD
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	45500	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	12.29
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	0	USD
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	274000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	10.38
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y9M
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	6493000	USD
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	20000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	8.25
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	0	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	224000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	10.86
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P4Y11M1D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	3789000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	224000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	10.86
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P4Y11M1D
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	3789000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1600000	USD
CY2020	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent Of Match DefinedContributionPlanEmployerMatchingContributionPercentOfMatch	0.50
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	2000000.0	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1800000	USD
CY2020Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	11300000	USD
CY2019Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	9800000	USD
CY2020	us-gaap	Deferred Compensation Arrangement With Individual Compensation Expense DeferredCompensationArrangementWithIndividualCompensationExpense	1900000	USD
CY2019	us-gaap	Deferred Compensation Arrangement With Individual Compensation Expense DeferredCompensationArrangementWithIndividualCompensationExpense	1200000	USD
CY2018	us-gaap	Deferred Compensation Arrangement With Individual Compensation Expense DeferredCompensationArrangementWithIndividualCompensationExpense	1100000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	18157000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	14232000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	4562000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-11545000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-2513000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	5658000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1723000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1030000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	638000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-339000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-83000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-21000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7996000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12666000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10837000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	9314000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	13975000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	13113000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	878000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0198
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	644000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0097
CY2018	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	907000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.0145
CY2020	obnk	Effective Income Tax Rate Reconciliation Tax Credit Low Income Housing Net Of Amortization EffectiveIncomeTaxRateReconciliationTaxCreditLowIncomeHousingNetOfAmortization	511000	USD
CY2020	obnk	Effective Income Tax Rate Reconciliation Tax Credit Low Income Housing Net Of Amortization Percent EffectiveIncomeTaxRateReconciliationTaxCreditLowIncomeHousingNetOfAmortizationPercent	0.0115
CY2019	obnk	Effective Income Tax Rate Reconciliation Tax Credit Low Income Housing Net Of Amortization EffectiveIncomeTaxRateReconciliationTaxCreditLowIncomeHousingNetOfAmortization	514000	USD
CY2019	obnk	Effective Income Tax Rate Reconciliation Tax Credit Low Income Housing Net Of Amortization Percent EffectiveIncomeTaxRateReconciliationTaxCreditLowIncomeHousingNetOfAmortizationPercent	0.0077
CY2018	obnk	Effective Income Tax Rate Reconciliation Tax Credit Low Income Housing Net Of Amortization EffectiveIncomeTaxRateReconciliationTaxCreditLowIncomeHousingNetOfAmortization	691000	USD
CY2018	obnk	Effective Income Tax Rate Reconciliation Tax Credit Low Income Housing Net Of Amortization Percent EffectiveIncomeTaxRateReconciliationTaxCreditLowIncomeHousingNetOfAmortizationPercent	0.0111
CY2020	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	1218000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Other EffectiveIncomeTaxRateReconciliationTaxCreditsOther	0.0275
CY2019	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	1218000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Other EffectiveIncomeTaxRateReconciliationTaxCreditsOther	0.0183
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	1218000	USD
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	723000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Other EffectiveIncomeTaxRateReconciliationTaxCreditsOther	0.0195
CY2020	obnk	Effective Income Tax Reconciliation Tax Exempt Income Bank Owned Life Insurance Income EffectiveIncomeTaxReconciliationTaxExemptIncomeBankOwnedLifeInsuranceIncome	-259000	USD
CY2020	obnk	Effective Income Tax Reconciliation Tax Exempt Income Bank Owned Life Insurance Income Percent EffectiveIncomeTaxReconciliationTaxExemptIncomeBankOwnedLifeInsuranceIncomePercent	-0.0058
CY2019	obnk	Effective Income Tax Reconciliation Tax Exempt Income Bank Owned Life Insurance Income EffectiveIncomeTaxReconciliationTaxExemptIncomeBankOwnedLifeInsuranceIncome	-158000	USD
CY2019	obnk	Effective Income Tax Reconciliation Tax Exempt Income Bank Owned Life Insurance Income Percent EffectiveIncomeTaxReconciliationTaxExemptIncomeBankOwnedLifeInsuranceIncomePercent	-0.0024
CY2018	obnk	Effective Income Tax Reconciliation Tax Exempt Income Bank Owned Life Insurance Income EffectiveIncomeTaxReconciliationTaxExemptIncomeBankOwnedLifeInsuranceIncome	-150000	USD
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CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.0016
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CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.1804
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CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	1441000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	26123000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	14941000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	994000	USD
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CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	13971000	USD
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CY2019Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	4472000	USD
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CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	152000	USD
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CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	7450000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	18825000	USD
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CY2018	obnk	Tax Cuts And Jobs Act Reclassification From Aoci To Retained Earnings Tax Effect Current TaxCutsAndJobsActReclassificationFromAOCIToRetainedEarningsTaxEffectCurrent	-276000	USD
CY2018	obnk	Tax Cuts And Jobs Act Reclassification From Aoci To Retained Earnings Tax Effect Deferred TaxCutsAndJobsActReclassificationFromAOCIToRetainedEarningsTaxEffectDeferred	558000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	8813000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	19316000	USD
CY2020	obnk	Benefit To Common Equity Tier1 Capital Risk Weighted Assets Capital Ratio BenefitToCommonEquityTier1CapitalRiskWeightedAssetsCapitalRatio	0.0019
CY2020Q1	obnk	Stock Repurchase Program Number Of Transactions StockRepurchaseProgramNumberOfTransactions	3	transaction
CY2020	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	30868	shares
CY2020	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	23.44
CY2020Q4	obnk	Stock Repurchase Program Cumulative Amount Repurchased StockRepurchaseProgramCumulativeAmountRepurchased	10100000	USD
CY2020Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	29200000	USD
CY2020Q4	us-gaap	Guarantee Obligations Current Carrying Value GuaranteeObligationsCurrentCarryingValue	200000	USD
CY2019Q4	us-gaap	Guarantee Obligations Current Carrying Value GuaranteeObligationsCurrentCarryingValue	489000	USD
CY2019Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	241300000	USD
CY2020Q4	us-gaap	Related Party Deposit Liabilities RelatedPartyDepositLiabilities	30400000	USD
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CY2020Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	59422000	USD
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CY2020Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	55016000	USD
CY2020Q4	us-gaap	Interest Expense InterestExpense	7603000	USD
CY2020Q3	us-gaap	Interest Expense InterestExpense	8183000	USD
CY2020Q2	us-gaap	Interest Expense InterestExpense	9174000	USD
CY2020Q1	us-gaap	Interest Expense InterestExpense	12206000	USD
CY2020Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	51819000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	50617000	USD
CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	46290000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	42810000	USD
CY2020Q4	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	6333000	USD
CY2020Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	13633000	USD
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CY2020Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	18531000	USD
CY2020Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	45486000	USD
CY2020Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	36984000	USD
CY2020Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	24887000	USD
CY2020Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	24279000	USD
CY2020Q4	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	15156000	USD
CY2020Q3	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	17750000	USD
CY2020Q2	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	19076000	USD
CY2020Q1	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	12090000	USD
CY2020Q4	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	225000	USD
CY2020Q3	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	301000	USD
CY2020Q2	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	0	USD
CY2020Q1	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	54000	USD
CY2020Q4	us-gaap	Noninterest Expense NoninterestExpense	38884000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	38734000	USD
CY2020Q2	us-gaap	Noninterest Expense NoninterestExpense	38220000	USD
CY2020Q1	us-gaap	Noninterest Expense NoninterestExpense	36097000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	21983000	USD
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CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	326000	USD
CY2020Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4431000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3206000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	786000	USD
CY2020Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-427000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	17552000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	13095000	USD
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CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	753000	USD
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.75
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.56
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CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.56
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.21
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.03
CY2019Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	56719000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	58806000	USD
CY2019Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	57063000	USD
CY2019Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	54494000	USD
CY2019Q4	us-gaap	Interest Expense InterestExpense	12624000	USD
CY2019Q1	us-gaap	Interest Expense InterestExpense	12468000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	44095000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	44622000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	42969000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	42026000	USD
CY2019Q4	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	2377000	USD
CY2019Q3	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	4201000	USD
CY2019Q2	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	1985000	USD
CY2019Q1	us-gaap	Provision For Loan Lease And Other Losses ProvisionForLoanLeaseAndOtherLosses	1005000	USD
CY2019Q4	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	41718000	USD
CY2019Q3	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	40421000	USD
CY2019Q2	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	40984000	USD
CY2019Q1	us-gaap	Interest Income Expense After Provision For Loan Loss InterestIncomeExpenseAfterProvisionForLoanLoss	41021000	USD
CY2019Q4	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	10818000	USD
CY2019Q3	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	12860000	USD
CY2019Q2	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	11176000	USD
CY2019Q1	obnk	Noninterest Income Net Of Debt Securities Realized Gain Loss NoninterestIncomeNetOfDebtSecuritiesRealizedGainLoss	11604000	USD
CY2019Q4	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	0	USD
CY2019Q3	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	20000	USD
CY2019Q2	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	0	USD
CY2019Q1	us-gaap	Debt Securities Realized Gain Loss DebtSecuritiesRealizedGainLoss	0	USD
CY2019Q4	us-gaap	Noninterest Expense NoninterestExpense	36534000	USD
CY2019Q3	us-gaap	Noninterest Expense NoninterestExpense	35064000	USD
CY2019Q2	us-gaap	Noninterest Expense NoninterestExpense	37095000	USD
CY2019Q1	us-gaap	Noninterest Expense NoninterestExpense	35381000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	16002000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	18237000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	15065000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	17244000	USD
CY2019Q4	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3175000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3620000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2782000	USD
CY2019Q1	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3089000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	12827000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	14617000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	12283000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	14155000	USD
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.55
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.62
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.52
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.60
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.55
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.62
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.52
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.60

Files In Submission

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2020 Q4 Form 10-K Financial Statement

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$OBK Origin Bancorp Inc Stock $obk

2020 Q4 Form 10-K Financial Statement

#000151691221000019 Filed on March 02, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$OBK
Origin Bancorp Inc Stock $obk