$ISTR
Investar Holding Corp Stock $istr

$istr Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000160265821000043 Filed on March 10, 2021

Income Statement

Concept	2020 Q4	2020	2019 Q4
Revenue		$74.47M	$23.52M
YoY Change		7.73%	18.01%
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	$1.180M	$4.570M	$940.0K
YoY Change	25.53%	32.08%	38.24%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$20.26M	$6.550M
YoY Change		-17.73%	27.93%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$5.740M	$17.34M	$4.175M
YoY Change	37.49%	-17.27%	0.75%
Income Tax	$1.200M	$3.450M	$844.0K
% Of Pretax Income	20.91%	19.9%	20.22%
Net Earnings	$4.540M	$13.89M	$3.331M
YoY Change	36.3%	-17.52%	-0.18%
Net Earnings / Revenue		18.65%	14.17%
Basic Earnings Per Share		$1.27	$0.33
Diluted Earnings Per Share	$426.7K	$1.27	$0.32
COMMON SHARES
Basic Shares Outstanding	10.62M shares	10.85M	9.933M shares
Diluted Shares Outstanding		10.87M

Balance Sheet

Concept	2020 Q4	2020	2019 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$35.37M		$44.70M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$56.30M	$56.30M	$50.92M
YoY Change	10.58%	10.61%	26.57%
Goodwill	$28.10M		$26.10M
YoY Change	7.66%
Intangibles	$100.0K		$100.0K
YoY Change	0.0%		0.0%
Long-Term Investments
YoY Change
Other Assets	$1.400M	$1.400M	$0.00
YoY Change			-100.0%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$2.321B	$2.321B	$2.149B
YoY Change	8.02%	8.02%	20.29%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$3.900M	$3.900M	$3.400M
YoY Change	14.71%	14.71%
Deferred Revenue
YoY Change
Short-Term Debt	$5.700M	$5.700M	$3.000M
YoY Change	90.0%	90.0%	50.0%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$15.10M	$13.20M	$15.90M
YoY Change	-5.03%	-7.69%	60.61%
LONG-TERM LIABILITIES
Long-Term Debt	$48.80M	$48.80M	$48.70M
YoY Change	0.21%	0.21%	102.07%
Other Long-Term Liabilities		$1.900M
YoY Change		18.75%
Total Long-Term Liabilities	$48.80M	$50.70M	$48.70M
YoY Change	0.21%	0.8%	102.07%
TOTAL LIABILITIES
Total Short-Term Liabilities	$15.10M	$13.20M	$15.90M
Total Long-Term Liabilities	$48.80M	$50.70M	$48.70M
Total Liabilities	$2.078B	$2.078B	$1.907B
YoY Change	8.96%	8.97%	18.87%
SHAREHOLDERS EQUITY
Retained Earnings	$71.39M		$60.20M
YoY Change	18.58%		31.66%
Common Stock	$170.1M		$179.9M
YoY Change	-5.44%		28.84%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$243.3M	$243.3M	$242.0M
YoY Change
Total Liabilities & Shareholders Equity	$2.321B	$2.321B	$2.149B
YoY Change	8.02%	8.02%	20.29%

Cashflow Statement

Concept	2020 Q4	2020	2019 Q4
OPERATING ACTIVITIES
Net Income	$4.540M	$13.89M	$3.331M
YoY Change	36.3%	-17.52%	-0.18%
Depreciation, Depletion And Amortization	$1.180M	$4.570M	$940.0K
YoY Change	25.53%	32.08%	38.24%
Cash From Operating Activities	$6.460M	$17.75M	$4.830M
YoY Change	33.75%	-4.41%	13.38%
INVESTING ACTIVITIES
Capital Expenditures	-$1.230M	-$7.590M	-$1.700M
YoY Change	-27.65%	-4.17%	60.38%
Acquisitions		$10.81M
YoY Change
Other Investing Activities	-$14.52M	-$140.6M	-$22.50M
YoY Change	-35.47%	47.71%	-60.86%
Cash From Investing Activities	-$15.75M	-$148.1M	-$24.19M
YoY Change	-34.89%	43.74%	-58.67%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$11.11M
YoY Change		-155.01%
Debt Paid & Issued, Net		$3.100M
YoY Change		-74.17%
Cash From Financing Activities	-5.890M	$121.1M	35.06M
YoY Change	-116.8%	8.05%	-24.81%
NET CHANGE
Cash From Operating Activities	6.460M	$17.75M	4.830M
Cash From Investing Activities	-15.75M	-$148.1M	-24.19M
Cash From Financing Activities	-5.890M	$121.1M	35.06M
Net Change In Cash	-15.18M	-$9.327M	15.70M
YoY Change	-196.69%	-133.85%	-305.5%
FREE CASH FLOW
Cash From Operating Activities	$6.460M	$17.75M	$4.830M
Capital Expenditures	-$1.230M	-$7.590M	-$1.700M
Free Cash Flow	$7.690M	$25.34M	$6.530M
YoY Change	17.76%	-4.33%	22.74%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
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CY2020	dei	Entity File Number EntityFileNumber	001-36522
CY2020	dei	Entity Registrant Name EntityRegistrantName	Investar Holding Corp
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	LA
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	27-1560715
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	10500 Coursey Blvd.
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CY2020	dei	Security12b Title Security12bTitle	Common stock, $1.00 par value per share
CY2020	dei	Trading Symbol TradingSymbol	ISTR
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CY2018	us-gaap	Labor And Related Expense LaborAndRelatedExpense	25469000	USD
CY2020	us-gaap	Occupancy Net OccupancyNet	2236000	USD
CY2019	us-gaap	Occupancy Net OccupancyNet	1837000	USD
CY2018	us-gaap	Occupancy Net OccupancyNet	1378000	USD
CY2020	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	3069000	USD
CY2019	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	2360000	USD
CY2018	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	2090000	USD
CY2020	us-gaap	Marketing Expense MarketingExpense	333000	USD
CY2019	us-gaap	Marketing Expense MarketingExpense	260000	USD
CY2018	us-gaap	Marketing Expense MarketingExpense	237000	USD
CY2020	us-gaap	Professional Fees ProfessionalFees	1519000	USD
CY2019	us-gaap	Professional Fees ProfessionalFees	1189000	USD
CY2018	us-gaap	Professional Fees ProfessionalFees	1051000	USD
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	1062000	USD
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	2090000	USD
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	1445000	USD
CY2020	us-gaap	Other Noninterest Expense OtherNoninterestExpense	10964000	USD
CY2019	us-gaap	Other Noninterest Expense OtherNoninterestExpense	8327000	USD
CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	7659000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	57131000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	48168000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	41882000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	17339000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	20958000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	17236000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3450000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4119000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3630000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	13889000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	16839000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	13606000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.27
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.68
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.41
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.27
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.66
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.39
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.25
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.23
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.17
CY2020	us-gaap	Net Income Loss NetIncomeLoss	13889000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	16839000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	13606000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	1068000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	1362000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-419000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	4017000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	5123000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-1576000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	481000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	56000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	3000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	1808000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	206000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	11000	USD
CY2020	istr	Other Comprehensive Tax Expense Benefit Of Unrealized Holding Gain Loss Related To Securities Transferred From Available For Sale To Held To Maturity OtherComprehensiveTaxExpenseBenefitOfUnrealizedHoldingGainLossRelatedToSecuritiesTransferredFromAvailableForSaleToHeldToMaturity	0	USD
CY2019	istr	Other Comprehensive Tax Expense Benefit Of Unrealized Holding Gain Loss Related To Securities Transferred From Available For Sale To Held To Maturity OtherComprehensiveTaxExpenseBenefitOfUnrealizedHoldingGainLossRelatedToSecuritiesTransferredFromAvailableForSaleToHeldToMaturity	0	USD
CY2018	istr	Other Comprehensive Tax Expense Benefit Of Unrealized Holding Gain Loss Related To Securities Transferred From Available For Sale To Held To Maturity OtherComprehensiveTaxExpenseBenefitOfUnrealizedHoldingGainLossRelatedToSecuritiesTransferredFromAvailableForSaleToHeldToMaturity	0	USD
CY2020	istr	Other Comprehensive Income Loss Amortization Of Unrealized Gains Losses On Security Transferred From Available For Sale Securities To Held To Maturity Net Of Tax OtherComprehensiveIncomeLossAmortizationOfUnrealizedGainsLossesOnSecurityTransferredFromAvailableForSaleSecuritiesToHeldToMaturityNetOfTax	-1000	USD
CY2019	istr	Other Comprehensive Income Loss Amortization Of Unrealized Gains Losses On Security Transferred From Available For Sale Securities To Held To Maturity Net Of Tax OtherComprehensiveIncomeLossAmortizationOfUnrealizedGainsLossesOnSecurityTransferredFromAvailableForSaleSecuritiesToHeldToMaturityNetOfTax	-1000	USD
CY2018	istr	Other Comprehensive Income Loss Amortization Of Unrealized Gains Losses On Security Transferred From Available For Sale Securities To Held To Maturity Net Of Tax OtherComprehensiveIncomeLossAmortizationOfUnrealizedGainsLossesOnSecurityTransferredFromAvailableForSaleSecuritiesToHeldToMaturityNetOfTax	-2000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	-610000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	14000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax	22000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	-2294000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	51000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax Parent OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTaxParent	84000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-86000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4967000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1505000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	13803000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	21806000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	12101000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	172729000	USD
CY2018	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	219000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	3368000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	1036000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.17
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1640000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1071000	USD
CY2018	istr	Tax Cuts And Jobs Act Reclassification From Aoci To Retained Earnings Tax Effect TaxCutsAndJobsActReclassificationFromAOCIToRetainedEarningsTaxEffect	557000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	13606000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1505000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	182262000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	1475000	USD
CY2019	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	28525000	USD
CY2019	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	18637000	USD
CY2019	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	283000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	8326000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	287000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.23
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	2362000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1430000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	16839000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	4967000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	241976000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	57000	USD
CY2020	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	314000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	11112000	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	46000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.25
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	2702000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1644000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	13889000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-86000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	243284000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	13889000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	16839000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	13606000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	4570000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	3462000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	2553000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	11160000	USD
CY2019	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	1908000	USD
CY2018	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	2570000	USD
CY2020	istr	Amortization Of Purchase Accounting Adjustments AmortizationOfPurchaseAccountingAdjustments	1112000	USD
CY2019	istr	Amortization Of Purchase Accounting Adjustments AmortizationOfPurchaseAccountingAdjustments	1425000	USD
CY2018	istr	Amortization Of Purchase Accounting Adjustments AmortizationOfPurchaseAccountingAdjustments	2180000	USD
CY2020	us-gaap	Real Estate Owned Valuation Allowance Provision1 RealEstateOwnedValuationAllowanceProvision1	30000	USD
CY2019	us-gaap	Real Estate Owned Valuation Allowance Provision1 RealEstateOwnedValuationAllowanceProvision1	18000	USD
CY2018	us-gaap	Real Estate Owned Valuation Allowance Provision1 RealEstateOwnedValuationAllowanceProvision1	567000	USD
CY2020	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-2825000	USD
CY2019	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-712000	USD
CY2018	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	-478000	USD
CY2020	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	2289000	USD
CY2019	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	262000	USD
CY2018	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	14000	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-38000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-11000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	98000	USD
CY2020	istr	Gain Losses On Sales Of Foreclosed Assets GainLossesOnSalesOfForeclosedAssets	12000	USD
CY2019	istr	Gain Losses On Sales Of Foreclosed Assets GainLossesOnSalesOfForeclosedAssets	2000	USD
CY2018	istr	Gain Losses On Sales Of Foreclosed Assets GainLossesOnSalesOfForeclosedAssets	-24000	USD
CY2020	istr	Federal Home Loan Bank Stock Dividends FederalHomeLoanBankStockDividends	134000	USD
CY2019	istr	Federal Home Loan Bank Stock Dividends FederalHomeLoanBankStockDividends	336000	USD
CY2018	istr	Federal Home Loan Bank Stock Dividends FederalHomeLoanBankStockDividends	239000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	1644000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	1430000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	1071000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1388000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	153000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	841000	USD
CY2020	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	894000	USD
CY2019	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	703000	USD
CY2018	us-gaap	Life Insurance Corporate Or Bank Owned Change In Value LifeInsuranceCorporateOrBankOwnedChangeInValue	628000	USD
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	71000	USD
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	53000	USD
CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	46000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	268000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	341000	USD
CY2018	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-267000	USD
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	5056000	USD
CY2019	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	1925000	USD
CY2018	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	865000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	953000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2015000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-995000	USD
CY2020	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-4372000	USD
CY2019	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	990000	USD
CY2018	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-2582000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	17749000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	18567000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	16412000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	56466000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	65834000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	7021000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	127123000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	110431000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	72258000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	64348000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	39578000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	30545000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1938000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1623000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Held To Maturity Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfHeldToMaturitySecurities	1884000	USD
CY2020	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	9283000	USD
CY2019	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	2986000	USD
CY2018	us-gaap	Proceeds From Sale Of Federal Home Loan Bank Stock ProceedsFromSaleOfFederalHomeLoanBankStock	1299000	USD
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	6165000	USD
CY2019	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	7040000	USD
CY2018	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	4265000	USD
CY2020	us-gaap	Payments To Acquire Loans Receivable PaymentsToAcquireLoansReceivable	124736000	USD
CY2019	us-gaap	Payments To Acquire Loans Receivable PaymentsToAcquireLoansReceivable	162025000	USD
CY2018	us-gaap	Payments To Acquire Loans Receivable PaymentsToAcquireLoansReceivable	141505000	USD
CY2020	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	158000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	5150000	USD
CY2018	us-gaap	Proceeds From Sale Of Other Real Estate ProceedsFromSaleOfOtherRealEstate	132000	USD
CY2020	us-gaap	Payments To Acquire Other Real Estate PaymentsToAcquireOtherRealEstate	0	USD
CY2019	us-gaap	Payments To Acquire Other Real Estate PaymentsToAcquireOtherRealEstate	0	USD
CY2018	us-gaap	Payments To Acquire Other Real Estate PaymentsToAcquireOtherRealEstate	257000	USD
CY2020	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	232000	USD
CY2019	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	0	USD
CY2018	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	0	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	0	USD
CY2018	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	19000	USD
CY2020	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	7590000	USD
CY2019	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	7918000	USD
CY2018	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	4936000	USD
CY2020	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	6000000	USD
CY2019	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	5023000	USD
CY2018	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	0	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	0	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	95000	USD
CY2018	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	119000	USD
CY2020	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	1762000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	0	USD
CY2018	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	0	USD
CY2020	istr	Distributions From Investments DistributionsFromInvestments	93000	USD
CY2019	istr	Distributions From Investments DistributionsFromInvestments	162000	USD
CY2018	istr	Distributions From Investments DistributionsFromInvestments	39000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	10809000	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	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-148143000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-103063000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-182401000	USD
CY2020	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	143318000	USD
CY2019	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	153403000	USD
CY2018	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	136644000	USD
CY2020	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	2658000	USD
CY2019	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-9329000	USD
CY2018	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-19936000	USD
CY2020	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	-8000000	USD
CY2019	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	-86400000	USD
CY2018	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	22900000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	23500000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	75000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	3100000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	12000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	58100000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	2686000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	2167000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1468000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	11112000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	8326000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	3368000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	28525000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2020	istr	Proceeds From Stock Options And Warrants Exercised ProceedsFromStockOptionsAndWarrantsExercised	46000	USD
CY2019	istr	Proceeds From Stock Options And Warrants Exercised ProceedsFromStockOptionsAndWarrantsExercised	287000	USD
CY2018	istr	Proceeds From Stock Options And Warrants Exercised ProceedsFromStockOptionsAndWarrantsExercised	1036000	USD
CY2020	istr	Proceeds From Subordinated Notes Net Of Issuance Costs ProceedsFromSubordinatedNotesNetOfIssuanceCosts	0	USD
CY2019	istr	Proceeds From Subordinated Notes Net Of Issuance Costs ProceedsFromSubordinatedNotesNetOfIssuanceCosts	24558000	USD
CY2018	istr	Proceeds From Subordinated Notes Net Of Issuance Costs ProceedsFromSubordinatedNotesNetOfIssuanceCosts	0	USD
CY2020	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	57000	USD
CY2019	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	USD
CY2018	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	121067000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	112051000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	152708000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-9327000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	27555000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-13281000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	44695000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	17140000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	30421000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	35368000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	44695000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	17140000	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	4336000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	4190000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	2555000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	20702000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	24396000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	16139000	USD
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	41000	USD
CY2019	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	133000	USD
CY2018	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	239000	USD
CY2020	istr	Transfer From Bank Premises And Equipment To Other Assets TransferFromBankPremisesAndEquipmentToOtherAssets	665000	USD
CY2019	istr	Transfer From Bank Premises And Equipment To Other Assets TransferFromBankPremisesAndEquipmentToOtherAssets	0	USD
CY2018	istr	Transfer From Bank Premises And Equipment To Other Assets TransferFromBankPremisesAndEquipmentToOtherAssets	0	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	segment
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates, and such differences could be material.</span></div><div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Material estimates that are particularly susceptible to significant change relate to the determination of the allowance for loan losses. While management uses available information to recognize losses on loans, future additions to the allowance may be necessary based on changes in local economic conditions. In addition, regulatory agencies, as an integral part of their examination process, periodically review the Company’s allowance for loan losses. Such agencies may require the Company to recognize additions to the allowance based on their judgments about information available to them at the time of their examination. Because of these factors, it is reasonably possible that the allowance for loan losses may change materially in the near term. However, the amount of the change that is reasonably possible cannot be estimated.</span></div><div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Other estimates that are susceptible to significant change in the near term relate to the allowance for off-balance sheet credit losses, the fair value of stock-based compensation awards, the determination of other-than-temporary impairments of securities, and the fair value of financial instruments and goodwill.</span></div><div style="margin-top:12pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The ongoing COVID-19 pandemic has made certain estimates more challenging, including those discussed above, as the pandemic is unprecedented in recent history, continues to evolve, and its future effects are impossible to predict with any certainty.</span></div>
CY2020Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	200000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	100000	USD
CY2020	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	1100000	USD
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	2100000	USD
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	ReclassificationsCertain reclassifications have been made to the 2019 and 2018 financial statements to conform to the 2020 presentation.
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	608000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	263913000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	4916000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	419000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	268410000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	258104000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	2480000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	779000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	259805000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	56466000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	65834000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	7021000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	2300000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	346000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	14480000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	35000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	11000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	21000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	12434000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	215000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	12649000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	14409000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Gain HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain	71000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Accumulated Unrecognized Holding Loss HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	70	security
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	34546000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	223000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	14771000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	196000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	49317000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	419000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	141	security
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	62100000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	430000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	17861000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	349000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	79961000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	779000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	1669000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1691000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	830000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	832000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	12937000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	13014000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	2745000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	2751000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	64159000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	64865000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	4650000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	4654000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	185148000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	188840000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	4209000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	4412000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	263913000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	268410000	USD
CY2020Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	12434000	USD
CY2020Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	12649000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	2174000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	2175000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	790000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	792000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	13525000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	13675000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	3575000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	3582000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	66551000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	66568000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	5122000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	5126000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	175854000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	177387000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	4922000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	4980000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	258104000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	259805000	USD
CY2019Q4	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	14409000	USD
CY2019Q4	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	14480000	USD
CY2020Q4	us-gaap	Cash Collateral For Borrowed Securities CashCollateralForBorrowedSecurities	84600000	USD
CY2019Q4	us-gaap	Cash Collateral For Borrowed Securities CashCollateralForBorrowedSecurities	89500000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1860318000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1691975000	USD
CY2020Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	1800000	USD
CY2019Q4	us-gaap	Unamortized Loan Commitment And Origination Fees And Unamortized Discounts Or Premiums UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums	2100000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	3200000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	900000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	1839754000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	11160000	USD
CY2020Q4	istr	Financing Receivable Recorded Investment Past Due And Nonaccrual Status FinancingReceivableRecordedInvestmentPastDueAndNonaccrualStatus	16407000	USD
CY2020Q4	istr	Financing Receivable Recorded Investment Acquired Impaired FinancingReceivableRecordedInvestmentAcquiredImpaired	4157000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1860318000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	1680335000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Nonaccrual Status FinancingReceivableRecordedInvestmentNonaccrualStatus	3046000	USD
CY2019Q4	istr	Financing Receivable Recorded Investment Past Due And Nonaccrual Status FinancingReceivableRecordedInvestmentPastDueAndNonaccrualStatus	7248000	USD
CY2019Q4	istr	Financing Receivable Recorded Investment Acquired Impaired FinancingReceivableRecordedInvestmentAcquiredImpaired	4392000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1691975000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1860318000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1691975000	USD
CY2020Q4	istr	Loan Participations And Whole Loans Sold To And Serviced For Others Not On Balance Sheet LoanParticipationsAndWholeLoansSoldToAndServicedForOthersNotOnBalanceSheet	53500000	USD
CY2019Q4	istr	Loan Participations And Whole Loans Sold To And Serviced For Others Not On Balance Sheet LoanParticipationsAndWholeLoansSoldToAndServicedForOthersNotOnBalanceSheet	82800000	USD
CY2020Q4	istr	Loan Participations And Whole Loans Sold To And Serviced For Others Unpaid Principal Balance LoanParticipationsAndWholeLoansSoldToAndServicedForOthersUnpaidPrincipalBalance	154000000.0	USD
CY2019Q4	istr	Loan Participations And Whole Loans Sold To And Serviced For Others Unpaid Principal Balance LoanParticipationsAndWholeLoansSoldToAndServicedForOthersUnpaidPrincipalBalance	174700000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	96400000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	98100000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	98093000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	93021000	USD
CY2020	us-gaap	Loans And Leases Receivable Related Parties Additions LoansAndLeasesReceivableRelatedPartiesAdditions	12443000	USD
CY2019	us-gaap	Loans And Leases Receivable Related Parties Additions LoansAndLeasesReceivableRelatedPartiesAdditions	20903000	USD
CY2020	us-gaap	Loans And Leases Receivable Related Parties Proceeds LoansAndLeasesReceivableRelatedPartiesProceeds	14146000	USD
CY2019	us-gaap	Loans And Leases Receivable Related Parties Proceeds LoansAndLeasesReceivableRelatedPartiesProceeds	15831000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	96390000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Related Parties LoansAndLeasesReceivableRelatedParties	98093000	USD
CY2019	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	0	USD
CY2020	us-gaap	Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Accretable Yield Additions CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAccretableYieldAdditions	0	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	10700000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	9454000	USD
CY2017Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	7891000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11160000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1908000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2570000	USD
CY2020	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1754000	USD
CY2019	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	800000	USD
CY2018	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1185000	USD
CY2020	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	257000	USD
CY2019	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	138000	USD
CY2018	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	178000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	20363000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	10700000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	9454000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	10700000	USD
CY2020	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1754000	USD
CY2020	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	257000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11160000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	20363000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	210000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	19943000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	19177000	USD
CY2020Q4	us-gaap	Notes Receivable Net NotesReceivableNet	4157000	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	1836984000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1860318000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	9454000	USD
CY2019	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	800000	USD
CY2019	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	138000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1908000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	10700000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	141000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	10559000	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	2547000	USD
CY2019Q4	us-gaap	Notes Receivable Net NotesReceivableNet	4392000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	1685036000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1691975000	USD
CY2017Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	7891000	USD
CY2018	us-gaap	Allowance For Loan And Lease Losses Write Offs AllowanceForLoanAndLeaseLossesWriteOffs	1185000	USD
CY2018	us-gaap	Allowance For Loan And Lease Loss Recovery Of Bad Debts AllowanceForLoanAndLeaseLossRecoveryOfBadDebts	178000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	2570000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	9454000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	236000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	9218000	USD
CY2018Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	3269000	USD
CY2018Q4	us-gaap	Notes Receivable Net NotesReceivableNet	6017000	USD
CY2018Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	1391539000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Gross Carrying Amount LoansAndLeasesReceivableGrossCarryingAmount	1400825000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	18695000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	19970000	USD
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	11356000	USD
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Cash Basis Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod	197000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	482000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	525000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	210000	USD
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	278000	USD
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Cash Basis Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod	1000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	19177000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	20495000	USD
CY2019	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	2932000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	210000	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	11634000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	198000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	2237000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	2365000	USD
CY2019	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Cash Basis Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod	53000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	310000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	347000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	141000	USD
CY2019	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	324000	USD
CY2019	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Cash Basis Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod	0	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	2547000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	2712000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	141000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	3256000	USD
CY2019	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	53000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	2568000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	2630000	USD
CY2018	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	3258000	USD
CY2018	us-gaap	Impaired Financing Receivable With No Related Allowance Interest Income Cash Basis Method ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod	72000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	701000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	738000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	236000	USD
CY2018	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	588000	USD
CY2018	us-gaap	Impaired Financing Receivable With Related Allowance Interest Income Cash Basis Method ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod	0	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	3269000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	3368000	USD
CY2018Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	236000	USD
CY2018	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	3846000	USD
CY2018	us-gaap	Impaired Financing Receivable Interest Income Cash Basis Method ImpairedFinancingReceivableInterestIncomeCashBasisMethod	72000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	34	security_loan
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	14700000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	18	security_loan
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	1500000	USD
CY2020Q4	istr	Financing Receivable Modifications Subsequent Default Nonaccrual Status Number Of Contracts FinancingReceivableModificationsSubsequentDefaultNonaccrualStatusNumberOfContracts	0	contract
CY2019Q4	istr	Financing Receivable Modifications Subsequent Default Nonaccrual Status Number Of Contracts FinancingReceivableModificationsSubsequentDefaultNonaccrualStatusNumberOfContracts	2	contract
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	13626000	USD
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	13626000	USD
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	0	USD
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	0	USD
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	contract
CY2020Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	14650000	USD
CY2019Q4	us-gaap	Financing Receivable Modifications Recorded Investment FinancingReceivableModificationsRecordedInvestment	1483000	USD
CY2020	istr	Other Real Estate Owned Acquired OtherRealEstateOwnedAcquired	0	USD
CY2019Q4	us-gaap	Foreclosed Assets ForeclosedAssets	133000	USD
CY2018Q4	us-gaap	Foreclosed Assets ForeclosedAssets	3611000	USD
CY2020	istr	Other Real Estate Owned Transfers From Non Acquired Loans OtherRealEstateOwnedTransfersFromNonAcquiredLoans	41000	USD
CY2019	istr	Other Real Estate Owned Transfers From Non Acquired Loans OtherRealEstateOwnedTransfersFromNonAcquiredLoans	181000	USD
CY2020	istr	Other Real Estate Owned Bank Premises And Equipment Transferred In OtherRealEstateOwnedBankPremisesAndEquipmentTransferredIn	665000	USD
CY2019	istr	Other Real Estate Owned Bank Premises And Equipment Transferred In OtherRealEstateOwnedBankPremisesAndEquipmentTransferredIn	0	USD
CY2019	istr	Other Real Estate Owned Acquired OtherRealEstateOwnedAcquired	1507000	USD
CY2020	istr	Other Real Estate Owned Other Real Estate Sold OtherRealEstateOwnedOtherRealEstateSold	146000	USD
CY2019	istr	Other Real Estate Owned Other Real Estate Sold OtherRealEstateOwnedOtherRealEstateSold	5148000	USD
CY2020	istr	Other Real Estate Owned Write Downs OtherRealEstateOwnedWriteDowns	30000	USD
CY2019	istr	Other Real Estate Owned Write Downs OtherRealEstateOwnedWriteDowns	18000	USD
CY2020Q4	us-gaap	Foreclosed Assets ForeclosedAssets	663000	USD
CY2019Q4	us-gaap	Foreclosed Assets ForeclosedAssets	133000	USD
CY2020Q4	us-gaap	Mortgage Loans In Process Of Foreclosure Amount MortgageLoansInProcessOfForeclosureAmount	1700000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Before Accumulated Amortization FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization	3851000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset Before Accumulated Amortization FinanceLeaseRightOfUseAssetBeforeAccumulatedAmortization	3309000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	15830000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	663000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	554000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization	12432000	USD
CY2020Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	56303000	USD
CY2019Q4	us-gaap	Property Plant And Equipment And Finance Lease Right Of Use Asset After Accumulated Depreciation And Amortization PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization	50916000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	599000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	341000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y7M6D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y4M24D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.028
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.031
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	3900000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	3900000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	28100000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	593000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	598000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	595000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	515000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	476000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1691000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	4468000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	200000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	8000	USD
CY2020Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	32200000	USD
CY2019Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	31000000.0	USD
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2019Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	444000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	26100000	USD
CY2020Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	100000	USD
CY2019Q4	us-gaap	Indefinite Lived Trademarks IndefiniteLivedTrademarks	100000	USD
CY2020Q4	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	6637000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	6467000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	2649000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1664000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	3988000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	4803000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	882000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	773000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	672000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	3988000	USD
CY2020Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	448230000	USD
CY2019Q4	us-gaap	Noninterest Bearing Deposit Liabilities NoninterestBearingDepositLiabilities	351905000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Demand InterestBearingDomesticDepositDemand	496745000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Demand InterestBearingDomesticDepositDemand	335478000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	80017000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Brokered InterestBearingDomesticDepositBrokered	0	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	186307000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	198999000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	141134000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	115324000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Time Deposits InterestBearingDomesticDepositTimeDeposits	535391000	USD
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Time Deposits InterestBearingDomesticDepositTimeDeposits	706000000	USD
CY2020Q4	us-gaap	Deposits Deposits	1887824000	USD
CY2019Q4	us-gaap	Deposits Deposits	1707706000	USD
CY2020Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	161957000	USD
CY2019Q4	us-gaap	Time Deposits Less Than100000 TimeDepositsLessThan100000	225951000	USD
CY2020Q4	istr	Time Deposits100000 To249999 TimeDeposits100000To249999	274470000	USD
CY2019Q4	istr	Time Deposits100000 To249999 TimeDeposits100000To249999	345040000	USD
CY2020Q4	istr	Time Deposits250000 And Above TimeDeposits250000AndAbove	98964000	USD
CY2019Q4	istr	Time Deposits250000 And Above TimeDeposits250000AndAbove	135009000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	535391000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	706000000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Or Less ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsOrLess	80605000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Or Less ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsOrLess	92157000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Through Six Months ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsThroughSixMonths	75974000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Through Six Months ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsThroughSixMonths	76179000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Six Months Through12 Months ContractualMaturitiesTimeDeposits100000OrMoreSixMonthsThrough12Months	111879000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Six Months Through12 Months ContractualMaturitiesTimeDeposits100000OrMoreSixMonthsThrough12Months	200654000	USD
CY2020Q4	istr	Contractual Maturities Time Deposits100000 Or More One Year Through Three Years ContractualMaturitiesTimeDeposits100000OrMoreOneYearThroughThreeYears	94178000	USD
CY2019Q4	istr	Contractual Maturities Time Deposits100000 Or More One Year Through Three Years ContractualMaturitiesTimeDeposits100000OrMoreOneYearThroughThreeYears	95495000	USD
CY2020Q4	istr	Contractual Maturities Time Deposits100000 Or More After Three Years ContractualMaturitiesTimeDeposits100000OrMoreAfterThreeYears	10798000	USD
CY2019Q4	istr	Contractual Maturities Time Deposits100000 Or More After Three Years ContractualMaturitiesTimeDeposits100000OrMoreAfterThreeYears	15564000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	373434000	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	480049000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	103488000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	33247000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	382713000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	10785000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	5158000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	535391000	USD
CY2020Q4	istr	Deposits Public Funds Amount DepositsPublicFundsAmount	86600000	USD
CY2019Q4	istr	Deposits Public Funds Amount DepositsPublicFundsAmount	103400000	USD
CY2020Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	72700000	USD
CY2019Q4	us-gaap	Security Owned And Pledged As Collateral Fair Value SecurityOwnedAndPledgedAsCollateralFairValue	89400000	USD
CY2020Q4	us-gaap	Related Party Deposit Liabilities RelatedPartyDepositLiabilities	38800000	USD
CY2019Q4	us-gaap	Related Party Deposit Liabilities RelatedPartyDepositLiabilities	76300000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	5700000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	3000000.0	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase Fair Value Of Collateral SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral	6300000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase Fair Value Of Collateral SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral	2900000	USD
CY2020Q4	us-gaap	Assets Sold Under Agreements To Repurchase Interest Rate AssetsSoldUnderAgreementsToRepurchaseInterestRate	0.0020
CY2019Q4	us-gaap	Assets Sold Under Agreements To Repurchase Interest Rate AssetsSoldUnderAgreementsToRepurchaseInterestRate	0.0075
CY2020Q4	istr	Assets Soldunder Agreementsto Repurchase Weighted Average Interest Rate AssetsSoldunderAgreementstoRepurchaseWeightedAverageInterestRate	0.0030
CY2019Q4	istr	Assets Soldunder Agreementsto Repurchase Weighted Average Interest Rate AssetsSoldunderAgreementstoRepurchaseWeightedAverageInterestRate	0.0132
CY2018Q4	istr	Assets Soldunder Agreementsto Repurchase Weighted Average Interest Rate AssetsSoldunderAgreementstoRepurchaseWeightedAverageInterestRate	0.0099
CY2019Q4	us-gaap	Subordinated Debt SubordinatedDebt	42800000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	0	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	53100000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Of Amounts Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueWithinOneYearOfBalanceSheetDate	0
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Of Amounts Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueWithinOneYearOfBalanceSheetDate	0.0174
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From One To Two Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate	42000000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From One To Two Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate	0	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate One To Two Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOneToTwoYearsFromBalanceSheetDate	0.0011
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate One To Two Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOneToTwoYearsFromBalanceSheetDate	0
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	23500000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	23500000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Two To Three Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateTwoToThreeYearsFromBalanceSheetDate	0.0181
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Two To Three Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateTwoToThreeYearsFromBalanceSheetDate	0.0181
CY2020Q4	istr	Federal Home Loan Bank Advances Maturities Summary Due In Year Ten FederalHomeLoanBankAdvancesMaturitiesSummaryDueInYearTen	25000000	USD
CY2019Q4	istr	Federal Home Loan Bank Advances Maturities Summary Due In Year Ten FederalHomeLoanBankAdvancesMaturitiesSummaryDueInYearTen	25000000	USD
CY2020Q4	istr	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Nine To Ten Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateNineToTenYearsFromBalanceSheetDate	0.0177
CY2019Q4	istr	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Nine To Ten Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateNineToTenYearsFromBalanceSheetDate	0.0177
CY2020Q4	istr	Federal Home Loan Bank Advances Maturities Summary Due In Year Eleven FederalHomeLoanBankAdvancesMaturitiesSummaryDueInYearEleven	30000000	USD
CY2019Q4	istr	Federal Home Loan Bank Advances Maturities Summary Due In Year Eleven FederalHomeLoanBankAdvancesMaturitiesSummaryDueInYearEleven	30000000	USD
CY2020Q4	istr	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Ten To Eleven Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateTenToElevenYearsFromBalanceSheetDate	0.0188
CY2019Q4	istr	Federal Home Loan Bank Advances Maturities Summary Average Interest Rate Ten To Eleven Years From Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateTenToElevenYearsFromBalanceSheetDate	0.0188
CY2020Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	120500000	USD
CY2019Q4	us-gaap	Advances From Federal Home Loan Banks AdvancesFromFederalHomeLoanBanks	131600000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Interest Rate FederalHomeLoanBankAdvancesBranchOfFHLBBankInterestRate	0.0123
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Interest Rate FederalHomeLoanBankAdvancesBranchOfFHLBBankInterestRate	0.0179
CY2020Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Amount Of Available Unused Funds FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresAmountOfAvailableUnusedFunds	654900000	USD
CY2020Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	5949000	USD
CY2020Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	5900000	USD
CY2019Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	5900000	USD
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	5000000	shares
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	40000000	shares
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	40000000	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	10608869	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	11228775	shares
CY2018Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	9484219	shares
CY2020Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	44300000	USD
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	322917	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	15.09
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y2M8D
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	31788	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	20.25
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	1644	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	14.00
CY2018	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	12415	shares
CY2018	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	14.07
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	340646	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	15.98
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y5M26D
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	36984	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	24.40
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	0	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	0
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	20416	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	14.06
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	357214	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	16.96
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P5Y11M4D
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	58993	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	16.96
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	4585	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	21.36
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	3334	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	14.00
CY2019	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	200000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	15.67
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P4Y5M19D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	500000	USD
CY2020	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	200000	USD
CY2019	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	300000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	408288	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	17.66
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P5Y6M25D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	276855	shares
CY2018	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	300000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions	600000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0112
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate	0.0082
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.2639
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate	0.2726
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0099
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate	0.0263
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y6M
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1	P6Y6M
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	5.17
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	7.30
CY2020	istr	Minimum Service Period For Participation In Defined Benefit Plan MinimumServicePeriodForParticipationInDefinedBenefitPlan	P3M
CY2020	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.04
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	900000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	800000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	700000	USD
CY2020	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	200000	USD
CY2020	istr	Defined Contribution Plan Employers Discretionary Contribution Annual Vesting Percentage DefinedContributionPlanEmployersDiscretionaryContributionAnnualVestingPercentage	0.20
CY2020	istr	Defined Contribution Plan Employer Discretionary Contribution Amount Award Vesting Period DefinedContributionPlanEmployerDiscretionaryContributionAmountAwardVestingPeriod	P5Y
CY2020	istr	Defined Contribution Plan Award Requisite Service Period DefinedContributionPlanAwardRequisiteServicePeriod	P2Y
CY2020	istr	Defined Contribution Plan Employer Discretionary Contribution Amount Total Award Vesting Period DefinedContributionPlanEmployerDiscretionaryContributionAmountTotalAwardVestingPeriod	P6Y
CY2020Q4	istr	Deferred Compensation Arrangement With Individual Monthly Distribution DeferredCompensationArrangementWithIndividualMonthlyDistribution	2000	USD
CY2020Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	1900000	USD
CY2019Q4	us-gaap	Deferred Compensation Liability Current And Noncurrent DeferredCompensationLiabilityCurrentAndNoncurrent	1600000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	4838000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	3966000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	2789000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-1388000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	153000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	841000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3450000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	249000	USD
CY2020	istr	Effective Income Tax Rate Reconciliation Acquisition Costs Amount EffectiveIncomeTaxRateReconciliationAcquisitionCostsAmount	0	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	250000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4119000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3630000	USD
CY2018	us-gaap	Tax Cuts And Jobs Act Of2017 Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncomeTaxExpenseBenefit	300000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	3641000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	4401000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	3619000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	299000	USD
CY2019	istr	Effective Income Tax Rate Reconciliation Acquisition Costs Amount EffectiveIncomeTaxRateReconciliationAcquisitionCostsAmount	32000	USD
CY2018	istr	Effective Income Tax Rate Reconciliation Acquisition Costs Amount EffectiveIncomeTaxRateReconciliationAcquisitionCostsAmount	29000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Depreciation IncomeTaxReconciliationNondeductibleExpenseDepreciation	29000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Depreciation IncomeTaxReconciliationNondeductibleExpenseDepreciation	6000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	0	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Depreciation IncomeTaxReconciliationNondeductibleExpenseDepreciation	6000	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	338000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	33000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	15000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	46000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-85000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-113000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3450000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	4119000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3630000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.199
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.197
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.211
CY2019Q4	istr	Deferred Tax Liabilities Federal Home Loan Bank Stock Dividend DeferredTaxLiabilitiesFederalHomeLoanBankStockDividend	122000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3746000	USD
CY2019Q4	istr	Deferred Tax Liabilities Basis Difference In Acquired Assets And Liabilities DeferredTaxLiabilitiesBasisDifferenceInAcquiredAssetsAndLiabilities	1123000	USD
CY2020Q4	istr	Deferred Tax Liabilities Operating Lease Rightofuse Asset DeferredTaxLiabilitiesOperatingLeaseRightofuseAsset	809000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	2903000	USD
CY2020Q4	istr	Deferred Tax Liabilities Federal Home Loan Bank Stock Dividend DeferredTaxLiabilitiesFederalHomeLoanBankStockDividend	63000	USD
CY2019Q4	istr	Deferred Tax Liabilities Operating Lease Rightofuse Asset DeferredTaxLiabilitiesOperatingLeaseRightofuseAsset	695000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	564000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	404000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	480000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other Comprehensive Income DeferredTaxLiabilitiesOtherComprehensiveIncome	502000	USD
CY2020Q4	istr	Deferred Tax Liabilities Basis Difference In Acquired Assets And Liabilities DeferredTaxLiabilitiesBasisDifferenceInAcquiredAssetsAndLiabilities	1010000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	149000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	88000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	6257000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	5433000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	4012000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	2219000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	440000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	372000	USD
CY2020Q4	istr	Deferred Tax Assets Basis Difference In Acquired Assets And Liabilities DeferredTaxAssetsBasisDifferenceInAcquiredAssetsAndLiabilities	380000	USD
CY2019Q4	istr	Deferred Tax Assets Basis Difference In Acquired Assets And Liabilities DeferredTaxAssetsBasisDifferenceInAcquiredAssetsAndLiabilities	481000	USD
CY2020Q4	istr	Deferred Tax Assets Historical Tax Credit DeferredTaxAssetsHistoricalTaxCredit	0	USD
CY2019Q4	istr	Deferred Tax Assets Historical Tax Credit DeferredTaxAssetsHistoricalTaxCredit	155000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	524000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	419000	USD
CY2020Q4	istr	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	828000	USD
CY2019Q4	istr	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	709000	USD
CY2020Q4	istr	Deferred Tax Assets Unearned Loan Fees DeferredTaxAssetsUnearnedLoanFees	667000	USD
CY2019Q4	istr	Deferred Tax Assets Unearned Loan Fees DeferredTaxAssetsUnearnedLoanFees	190000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	362000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	229000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	7617000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	5338000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	1360000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	95000	USD
CY2020Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	2100000	USD
CY2019Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	2700000	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	20143000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	590000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	USD
CY2019	istr	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Paydowns FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaydowns	23000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	1335000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	19375000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-859000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	USD
CY2020	istr	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Paydowns FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaydowns	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	0	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	18516000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2018	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2019Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	200000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Impaired Commitment To Lend LoansAndLeasesReceivableImpairedCommitmentToLend	100000	USD
CY2020Q4	istr	Commitment To Fund Investment In Sbic Qualified Funds CommitmentToFundInvestmentInSBICQualifiedFunds	1000000.0	USD
CY2020Q3	istr	Employment Agreement Automatic Renewal Period EmploymentAgreementAutomaticRenewalPeriod	P1Y
CY2020Q3	istr	Employment Agreement Notice Required For Non Renewal Term EmploymentAgreementNoticeRequiredForNonRenewalTerm	P90D
CY2020	us-gaap	Net Income Loss NetIncomeLoss	13889000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	16839000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	13606000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	9931497	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	9538891	shares
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	13417000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	10850936	shares
CY2020	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	73000	USD
CY2019	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	164000	USD
CY2018	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	192000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	13816000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	16675000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	13414000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	10850936	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.27
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.68
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.41
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	13816000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	16676000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	9931497	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	9664843	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	9538891	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	14911	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	99521	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	125952	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	10865847	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	10031018	shares
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.27
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.66
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.39

Files In Submission

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$ISTR
Investar Holding Corp Stock $istr

2020 Q4 Form 10-K Financial Statement

#000160265821000043 Filed on March 10, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ISTR Investar Holding Corp Stock $istr

2020 Q4 Form 10-K Financial Statement

#000160265821000043 Filed on March 10, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ISTR
Investar Holding Corp Stock $istr