2022 Q3 Form 10-Q Financial Statement
#000086041322000191 Filed on August 05, 2022
Income Statement
Concept | 2022 Q3 | 2022 Q2 | 2022 Q1 |
---|---|---|---|
Revenue | $286.7M | $245.3M | $184.0M |
YoY Change | 118.69% | 98.95% | 46.85% |
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 | $13.90M | $14.20M | $13.30M |
YoY Change | 25.23% | 30.28% | 16.67% |
% of Gross Profit | |||
Operating Expenses | |||
YoY Change | |||
Operating Profit | |||
YoY Change | |||
Interest Expense | $19.90M | $7.400M | $6.000M |
YoY Change | 373.81% | 64.44% | 30.43% |
% of Operating Profit | |||
Other Income/Expense, Net | |||
YoY Change | |||
Pretax Income | $108.1M | $80.30M | -$41.30M |
YoY Change | 78.09% | 45.74% | -163.05% |
Income Tax | $22.40M | $16.20M | -$7.900M |
% Of Pretax Income | 20.72% | 20.17% | |
Net Earnings | $85.70M | $64.10M | -$33.40M |
YoY Change | 81.95% | 50.82% | -164.98% |
Net Earnings / Revenue | 29.89% | 26.13% | -18.15% |
Basic Earnings Per Share | $0.80 | $0.59 | -$0.36 |
Diluted Earnings Per Share | $804.0K | $0.59 | -$0.36 |
COMMON SHARES | |||
Basic Shares Outstanding | 106.8M shares | 109.1M shares | 92.86M shares |
Diluted Shares Outstanding | 106.6M shares | 109.1M shares | 92.86M shares |
Balance Sheet
Concept | 2022 Q3 | 2022 Q2 | 2022 Q1 |
---|---|---|---|
SHORT-TERM ASSETS | |||
Cash & Short-Term Investments | |||
YoY Change | |||
Cash & Equivalents | $591.9M | $1.059B | $3.811B |
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 | $445.4M | $442.7M | $444.4M |
YoY Change | 49.82% | 48.01% | 45.47% |
Goodwill | $1.100B | $1.100B | $1.138B |
YoY Change | 76.96% | 76.93% | 83.01% |
Intangibles | |||
YoY Change | |||
Long-Term Investments | |||
YoY Change | |||
Other Assets | $223.8M | $176.9M | $137.4M |
YoY Change | |||
Total Long-Term Assets | |||
YoY Change | |||
TOTAL ASSETS | |||
Total Short-Term Assets | |||
Total Long-Term Assets | |||
Total Assets | $31.34B | $32.06B | $33.16B |
YoY Change | 61.8% | 69.28% | 79.81% |
SHORT-TERM LIABILITIES | |||
YoY Change | |||
Accounts Payable | $7.400M | $4.300M | $6.000M |
YoY Change | 5.71% | -14.0% | -14.29% |
Accrued Expenses | |||
YoY Change | |||
Deferred Revenue | |||
YoY Change | |||
Short-Term Debt | $1.701B | $1.235B | $1.071B |
YoY Change | 68.71% | 18.84% | 1.71% |
Long-Term Debt Due | |||
YoY Change | |||
Total Short-Term Liabilities | $452.9M | $4.300M | $266.1M |
YoY Change | 210.21% | -14.0% | 3701.43% |
LONG-TERM LIABILITIES | |||
Long-Term Debt | $283.8M | $283.5M | $283.5M |
YoY Change | 42.61% | 42.46% | 42.46% |
Other Long-Term Liabilities | $470.0M | $6.100M | $6.200M |
YoY Change | 15566.67% | 103.33% | 106.67% |
Total Long-Term Liabilities | $753.8M | $289.6M | $289.7M |
YoY Change | 273.17% | 43.37% | 43.42% |
TOTAL LIABILITIES | |||
Total Short-Term Liabilities | $452.9M | $4.300M | $266.1M |
Total Long-Term Liabilities | $753.8M | $289.6M | $289.7M |
Total Liabilities | $28.34B | $28.79B | $29.72B |
YoY Change | 62.99% | 69.66% | 80.02% |
SHAREHOLDERS EQUITY | |||
Retained Earnings | $1.036B | $993.8M | $974.5M |
YoY Change | 0.87% | -1.13% | -1.39% |
Common Stock | |||
YoY Change | |||
Preferred Stock | |||
YoY Change | |||
Treasury Stock (at cost) | |||
YoY Change | |||
Treasury Stock Shares | |||
Shareholders Equity | $3.006B | $3.272B | $3.441B |
YoY Change | |||
Total Liabilities & Shareholders Equity | $31.34B | $32.06B | $33.16B |
YoY Change | 61.8% | 69.28% | 79.81% |
Cashflow Statement
Concept | 2022 Q3 | 2022 Q2 | 2022 Q1 |
---|---|---|---|
OPERATING ACTIVITIES | |||
Net Income | $85.70M | $64.10M | -$33.40M |
YoY Change | 81.95% | 50.82% | -164.98% |
Depreciation, Depletion And Amortization | $13.90M | $14.20M | $13.30M |
YoY Change | 25.23% | 30.28% | 16.67% |
Cash From Operating Activities | $169.4M | $204.3M | $64.90M |
YoY Change | 70.59% | 473.88% | -7.94% |
INVESTING ACTIVITIES | |||
Capital Expenditures | -$11.70M | -$6.000M | -$9.500M |
YoY Change | 125.0% | -3100.0% | 1800.0% |
Acquisitions | |||
YoY Change | |||
Other Investing Activities | -$137.9M | -$1.680B | $1.532B |
YoY Change | -28.92% | 134.72% | -259.8% |
Cash From Investing Activities | -$149.6M | -$1.686B | $1.523B |
YoY Change | -24.9% | 135.63% | -258.73% |
FINANCING ACTIVITIES | |||
Cash Dividend Paid | |||
YoY Change | |||
Common Stock Issuance & Retirement, Net | $1.300M | ||
YoY Change | -74.0% | ||
Debt Paid & Issued, Net | |||
YoY Change | |||
Cash From Financing Activities | -487.2M | -1.270B | -$120.9M |
YoY Change | -226.55% | -393.87% | -114.96% |
NET CHANGE | |||
Cash From Operating Activities | 169.4M | 204.3M | $64.90M |
Cash From Investing Activities | -149.6M | -1.686B | $1.523B |
Cash From Financing Activities | -487.2M | -1.270B | -$120.9M |
Net Change In Cash | -467.4M | -2.752B | $1.467B |
YoY Change | -263.94% | 1011.47% | -1914.98% |
FREE CASH FLOW | |||
Cash From Operating Activities | $169.4M | $204.3M | $64.90M |
Capital Expenditures | -$11.70M | -$6.000M | -$9.500M |
Free Cash Flow | $181.1M | $210.3M | $74.40M |
YoY Change | 73.3% | 494.07% | 4.79% |
Facts In Submission
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2022 | ||
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FIRST INTERSTATE BANCSYSTEM, INC. | ||
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|
15800000 | usd |
us-gaap |
Interest Income Securities Taxable
InterestIncomeSecuritiesTaxable
|
78100000 | usd | |
us-gaap |
Interest Income Securities Taxable
InterestIncomeSecuritiesTaxable
|
31600000 | usd | |
CY2022Q2 | us-gaap |
Interest Income Securities Tax Exempt
InterestIncomeSecuritiesTaxExempt
|
1400000 | usd |
CY2021Q2 | us-gaap |
Interest Income Securities Tax Exempt
InterestIncomeSecuritiesTaxExempt
|
1400000 | usd |
us-gaap |
Interest Income Securities Tax Exempt
InterestIncomeSecuritiesTaxExempt
|
2700000 | usd | |
us-gaap |
Interest Income Securities Tax Exempt
InterestIncomeSecuritiesTaxExempt
|
2800000 | usd | |
CY2022Q2 | us-gaap |
Interest Income Domestic Deposits
InterestIncomeDomesticDeposits
|
3400000 | usd |
CY2021Q2 | us-gaap |
Interest Income Domestic Deposits
InterestIncomeDomesticDeposits
|
700000 | usd |
us-gaap |
Interest Income Domestic Deposits
InterestIncomeDomesticDeposits
|
5100000 | usd | |
us-gaap |
Interest Income Domestic Deposits
InterestIncomeDomesticDeposits
|
1000000.0 | usd | |
CY2022Q2 | us-gaap |
Interest And Dividend Income Operating
InterestAndDividendIncomeOperating
|
245300000 | usd |
CY2021Q2 | us-gaap |
Interest And Dividend Income Operating
InterestAndDividendIncomeOperating
|
123300000 | usd |
us-gaap |
Interest And Dividend Income Operating
InterestAndDividendIncomeOperating
|
429300000 | usd | |
us-gaap |
Interest And Dividend Income Operating
InterestAndDividendIncomeOperating
|
248600000 | usd | |
CY2022Q2 | us-gaap |
Interest Expense Deposits
InterestExpenseDeposits
|
4300000 | usd |
CY2021Q2 | us-gaap |
Interest Expense Deposits
InterestExpenseDeposits
|
2200000 | usd |
us-gaap |
Interest Expense Deposits
InterestExpenseDeposits
|
7300000 | usd | |
us-gaap |
Interest Expense Deposits
InterestExpenseDeposits
|
4500000 | usd | |
CY2022Q2 | us-gaap |
Interest Expense Securities Sold Under Agreements To Repurchase
InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase
|
300000 | usd |
CY2021Q2 | us-gaap |
Interest Expense Securities Sold Under Agreements To Repurchase
InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase
|
100000 | usd |
us-gaap |
Interest Expense Securities Sold Under Agreements To Repurchase
InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase
|
600000 | usd | |
us-gaap |
Interest Expense Securities Sold Under Agreements To Repurchase
InterestExpenseSecuritiesSoldUnderAgreementsToRepurchase
|
200000 | usd | |
CY2022Q2 | us-gaap |
Interest Expense Other Long Term Debt
InterestExpenseOtherLongTermDebt
|
1400000 | usd |
CY2021Q2 | us-gaap |
Interest Expense Other Long Term Debt
InterestExpenseOtherLongTermDebt
|
1500000 | usd |
us-gaap |
Interest Expense Other Long Term Debt
InterestExpenseOtherLongTermDebt
|
3100000 | usd | |
us-gaap |
Interest Expense Other Long Term Debt
InterestExpenseOtherLongTermDebt
|
3000000.0 | usd | |
CY2022Q2 | us-gaap |
Interest Expense Junior Subordinated Debentures
InterestExpenseJuniorSubordinatedDebentures
|
1400000 | usd |
CY2021Q2 | us-gaap |
Interest Expense Junior Subordinated Debentures
InterestExpenseJuniorSubordinatedDebentures
|
700000 | usd |
us-gaap |
Interest Expense Junior Subordinated Debentures
InterestExpenseJuniorSubordinatedDebentures
|
2400000 | usd | |
us-gaap |
Interest Expense Junior Subordinated Debentures
InterestExpenseJuniorSubordinatedDebentures
|
1400000 | usd | |
CY2022Q2 | us-gaap |
Interest Expense
InterestExpense
|
7400000 | usd |
CY2021Q2 | us-gaap |
Interest Expense
InterestExpense
|
4500000 | usd |
us-gaap |
Interest Expense
InterestExpense
|
13400000 | usd | |
us-gaap |
Interest Expense
InterestExpense
|
9100000 | usd | |
CY2022Q2 | us-gaap |
Interest Income Expense Net
InterestIncomeExpenseNet
|
237900000 | usd |
CY2021Q2 | us-gaap |
Interest Income Expense Net
InterestIncomeExpenseNet
|
118800000 | usd |
us-gaap |
Interest Income Expense Net
InterestIncomeExpenseNet
|
415900000 | usd | |
us-gaap |
Interest Income Expense Net
InterestIncomeExpenseNet
|
239500000 | usd | |
CY2022Q2 | us-gaap |
Provision For Loan And Lease Losses
ProvisionForLoanAndLeaseLosses
|
-1700000 | usd |
CY2021Q2 | us-gaap |
Provision For Loan And Lease Losses
ProvisionForLoanAndLeaseLosses
|
0 | usd |
us-gaap |
Provision For Loan And Lease Losses
ProvisionForLoanAndLeaseLosses
|
59600000 | usd | |
us-gaap |
Provision For Loan And Lease Losses
ProvisionForLoanAndLeaseLosses
|
-5100000 | usd | |
CY2022Q2 | us-gaap |
Interest Income Expense After Provision For Loan Loss
InterestIncomeExpenseAfterProvisionForLoanLoss
|
239600000 | usd |
CY2021Q2 | us-gaap |
Interest Income Expense After Provision For Loan Loss
InterestIncomeExpenseAfterProvisionForLoanLoss
|
118800000 | usd |
us-gaap |
Interest Income Expense After Provision For Loan Loss
InterestIncomeExpenseAfterProvisionForLoanLoss
|
356300000 | usd | |
us-gaap |
Interest Income Expense After Provision For Loan Loss
InterestIncomeExpenseAfterProvisionForLoanLoss
|
244600000 | usd | |
CY2022Q2 | us-gaap |
Fees And Commissions Mortgage Banking And Servicing
FeesAndCommissionsMortgageBankingAndServicing
|
5000000.0 | usd |
CY2021Q2 | us-gaap |
Fees And Commissions Mortgage Banking And Servicing
FeesAndCommissionsMortgageBankingAndServicing
|
9600000 | usd |
us-gaap |
Fees And Commissions Mortgage Banking And Servicing
FeesAndCommissionsMortgageBankingAndServicing
|
13400000 | usd | |
us-gaap |
Fees And Commissions Mortgage Banking And Servicing
FeesAndCommissionsMortgageBankingAndServicing
|
21200000 | usd | |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Gain Loss
DebtSecuritiesAvailableForSaleGainLoss
|
-100000 | usd |
CY2021Q2 | us-gaap |
Debt Securities Available For Sale Gain Loss
DebtSecuritiesAvailableForSaleGainLoss
|
-100000 | usd |
us-gaap |
Debt Securities Available For Sale Gain Loss
DebtSecuritiesAvailableForSaleGainLoss
|
-200000 | usd | |
us-gaap |
Debt Securities Available For Sale Gain Loss
DebtSecuritiesAvailableForSaleGainLoss
|
-100000 | usd | |
CY2022Q2 | us-gaap |
Noninterest Income Other Operating Income
NoninterestIncomeOtherOperatingIncome
|
7400000 | usd |
CY2021Q2 | us-gaap |
Noninterest Income Other Operating Income
NoninterestIncomeOtherOperatingIncome
|
2600000 | usd |
us-gaap |
Noninterest Income Other Operating Income
NoninterestIncomeOtherOperatingIncome
|
13400000 | usd | |
us-gaap |
Noninterest Income Other Operating Income
NoninterestIncomeOtherOperatingIncome
|
6700000 | usd | |
CY2022Q2 | us-gaap |
Noninterest Income
NoninterestIncome
|
51000000.0 | usd |
CY2021Q2 | us-gaap |
Noninterest Income
NoninterestIncome
|
35300000 | usd |
us-gaap |
Noninterest Income
NoninterestIncome
|
100200000 | usd | |
us-gaap |
Noninterest Income
NoninterestIncome
|
73400000 | usd | |
CY2022Q2 | us-gaap |
Labor And Related Expense
LaborAndRelatedExpense
|
74800000 | usd |
CY2021Q2 | us-gaap |
Labor And Related Expense
LaborAndRelatedExpense
|
41600000 | usd |
us-gaap |
Labor And Related Expense
LaborAndRelatedExpense
|
134800000 | usd | |
us-gaap |
Labor And Related Expense
LaborAndRelatedExpense
|
80600000 | usd | |
CY2022Q2 | us-gaap |
Other Labor Related Expenses
OtherLaborRelatedExpenses
|
19400000 | usd |
CY2021Q2 | us-gaap |
Other Labor Related Expenses
OtherLaborRelatedExpenses
|
14700000 | usd |
us-gaap |
Other Labor Related Expenses
OtherLaborRelatedExpenses
|
40600000 | usd | |
us-gaap |
Other Labor Related Expenses
OtherLaborRelatedExpenses
|
30800000 | usd | |
CY2022Q2 | us-gaap |
Information Technology And Data Processing
InformationTechnologyAndDataProcessing
|
12800000 | usd |
CY2021Q2 | us-gaap |
Information Technology And Data Processing
InformationTechnologyAndDataProcessing
|
8400000 | usd |
us-gaap |
Information Technology And Data Processing
InformationTechnologyAndDataProcessing
|
24100000 | usd | |
us-gaap |
Information Technology And Data Processing
InformationTechnologyAndDataProcessing
|
16500000 | usd | |
CY2022Q2 | us-gaap |
Occupancy Net
OccupancyNet
|
11200000 | usd |
CY2021Q2 | us-gaap |
Occupancy Net
OccupancyNet
|
7100000 | usd |
us-gaap |
Occupancy Net
OccupancyNet
|
21200000 | usd | |
us-gaap |
Occupancy Net
OccupancyNet
|
14400000 | usd | |
CY2022Q2 | us-gaap |
Equipment Expense
EquipmentExpense
|
5800000 | usd |
CY2021Q2 | us-gaap |
Equipment Expense
EquipmentExpense
|
4100000 | usd |
us-gaap |
Equipment Expense
EquipmentExpense
|
11200000 | usd | |
us-gaap |
Equipment Expense
EquipmentExpense
|
8500000 | usd | |
CY2022Q2 | fibk |
Other Real Estate Owned Expense Net Of Income
OtherRealEstateOwnedExpenseNetOfIncome
|
0 | usd |
CY2021Q2 | fibk |
Other Real Estate Owned Expense Net Of Income
OtherRealEstateOwnedExpenseNetOfIncome
|
0 | usd |
fibk |
Other Real Estate Owned Expense Net Of Income
OtherRealEstateOwnedExpenseNetOfIncome
|
100000 | usd | |
fibk |
Other Real Estate Owned Expense Net Of Income
OtherRealEstateOwnedExpenseNetOfIncome
|
-100000 | usd | |
CY2022Q2 | us-gaap |
Professional Fees
ProfessionalFees
|
5500000 | usd |
CY2021Q2 | us-gaap |
Professional Fees
ProfessionalFees
|
3200000 | usd |
us-gaap |
Professional Fees
ProfessionalFees
|
9400000 | usd | |
us-gaap |
Professional Fees
ProfessionalFees
|
6600000 | usd | |
CY2022Q2 | us-gaap |
Federal Deposit Insurance Corporation Premium Expense
FederalDepositInsuranceCorporationPremiumExpense
|
2800000 | usd |
CY2021Q2 | us-gaap |
Federal Deposit Insurance Corporation Premium Expense
FederalDepositInsuranceCorporationPremiumExpense
|
1500000 | usd |
us-gaap |
Federal Deposit Insurance Corporation Premium Expense
FederalDepositInsuranceCorporationPremiumExpense
|
6100000 | usd | |
us-gaap |
Federal Deposit Insurance Corporation Premium Expense
FederalDepositInsuranceCorporationPremiumExpense
|
3100000 | usd | |
CY2022Q2 | us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
4100000 | usd |
CY2021Q2 | us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
2500000 | usd |
us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
7700000 | usd | |
us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
5000000.0 | usd | |
CY2022Q2 | us-gaap |
Other Noninterest Expense
OtherNoninterestExpense
|
28100000 | usd |
CY2021Q2 | us-gaap |
Other Noninterest Expense
OtherNoninterestExpense
|
15900000 | usd |
us-gaap |
Other Noninterest Expense
OtherNoninterestExpense
|
51300000 | usd | |
us-gaap |
Other Noninterest Expense
OtherNoninterestExpense
|
32000000.0 | usd | |
CY2022Q2 | us-gaap |
Business Combination Acquisition Related Costs
BusinessCombinationAcquisitionRelatedCosts
|
45800000 | usd |
CY2021Q2 | us-gaap |
Business Combination Acquisition Related Costs
BusinessCombinationAcquisitionRelatedCosts
|
0 | usd |
us-gaap |
Business Combination Acquisition Related Costs
BusinessCombinationAcquisitionRelatedCosts
|
111000000.0 | usd | |
us-gaap |
Business Combination Acquisition Related Costs
BusinessCombinationAcquisitionRelatedCosts
|
0 | usd | |
CY2022Q2 | us-gaap |
Noninterest Expense
NoninterestExpense
|
210300000 | usd |
CY2021Q2 | us-gaap |
Noninterest Expense
NoninterestExpense
|
99000000.0 | usd |
CY2022Q2 | us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
4100000 | usd |
us-gaap |
Noninterest Expense
NoninterestExpense
|
417500000 | usd | |
us-gaap |
Noninterest Expense
NoninterestExpense
|
197400000 | usd | |
CY2022Q2 | us-gaap |
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest
IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
|
80300000 | usd |
CY2021Q2 | us-gaap |
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest
IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
|
55100000 | usd |
us-gaap |
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest
IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
|
39000000.0 | usd | |
us-gaap |
Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest
IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
|
120600000 | usd | |
CY2022Q2 | us-gaap |
Income Tax Expense Benefit
IncomeTaxExpenseBenefit
|
16200000 | usd |
CY2021Q2 | us-gaap |
Income Tax Expense Benefit
IncomeTaxExpenseBenefit
|
12600000 | usd |
us-gaap |
Income Tax Expense Benefit
IncomeTaxExpenseBenefit
|
8300000 | usd | |
us-gaap |
Income Tax Expense Benefit
IncomeTaxExpenseBenefit
|
26700000 | usd | |
CY2022Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
64100000 | usd |
CY2021Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
42500000 | usd |
us-gaap |
Net Income Loss
NetIncomeLoss
|
30700000 | usd | |
us-gaap |
Net Income Loss
NetIncomeLoss
|
93900000 | usd | |
CY2022Q2 | us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
0.59 | |
CY2021Q2 | us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
0.69 | |
us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
0.30 | ||
us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
1.52 | ||
CY2022Q2 | us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
0.59 | |
CY2021Q2 | us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
0.69 | |
us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
0.30 | ||
us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
1.52 | ||
CY2022Q2 | us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
109106891 | shares |
CY2021Q2 | us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
61657593 | shares |
us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
101025926 | shares | |
us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
61624917 | shares | |
CY2022Q2 | us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
109131718 | shares |
CY2021Q2 | us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
61727821 | shares |
us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
101076331 | shares | |
us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
61723142 | shares | |
CY2022Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
64100000 | usd |
CY2021Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
42500000 | usd |
us-gaap |
Net Income Loss
NetIncomeLoss
|
30700000 | usd | |
us-gaap |
Net Income Loss
NetIncomeLoss
|
93900000 | usd | |
CY2022Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-161600000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-800000 | usd |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-414200000 | usd | |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-67600000 | usd | |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-100000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-100000 | usd |
us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-200000 | usd | |
us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-100000 | usd | |
CY2022Q2 | us-gaap |
Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax
OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax
|
0 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax
OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax
|
0 | usd |
us-gaap |
Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax
OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax
|
200000 | usd | |
us-gaap |
Other Comprehensive Income Reclassification Adjustment For Held To Maturity Transferred To Available For Sale Securities Before Tax
OtherComprehensiveIncomeReclassificationAdjustmentForHeldToMaturityTransferredToAvailableForSaleSecuritiesBeforeTax
|
0 | usd | |
CY2022Q2 | fibk |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Gain Loss Before Adjustment And Tax
OCIDebtSecuritiesAvailableForSaleTransferToHeldToMaturityGainLossBeforeAdjustmentAndTax
|
-900000 | usd |
CY2021Q2 | fibk |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Gain Loss Before Adjustment And Tax
OCIDebtSecuritiesAvailableForSaleTransferToHeldToMaturityGainLossBeforeAdjustmentAndTax
|
24800000 | usd |
fibk |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Gain Loss Before Adjustment And Tax
OCIDebtSecuritiesAvailableForSaleTransferToHeldToMaturityGainLossBeforeAdjustmentAndTax
|
-23900000 | usd | |
fibk |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Gain Loss Before Adjustment And Tax
OCIDebtSecuritiesAvailableForSaleTransferToHeldToMaturityGainLossBeforeAdjustmentAndTax
|
24800000 | usd | |
CY2022Q2 | us-gaap |
Unrealized Gain Loss On Derivatives
UnrealizedGainLossOnDerivatives
|
-15000000.0 | usd |
CY2021Q2 | us-gaap |
Unrealized Gain Loss On Derivatives
UnrealizedGainLossOnDerivatives
|
-800000 | usd |
us-gaap |
Unrealized Gain Loss On Derivatives
UnrealizedGainLossOnDerivatives
|
6300000 | usd | |
us-gaap |
Unrealized Gain Loss On Derivatives
UnrealizedGainLossOnDerivatives
|
-900000 | usd | |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
-177400000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
23300000 | usd |
us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
-431400000 | usd | |
us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
-43600000 | usd | |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
-49600000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
5900000 | usd |
us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
-112600000 | usd | |
us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
-11100000 | usd | |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
-127800000 | usd |
CY2021Q2 | us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
2500000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
17400000 | usd |
us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
-318800000 | usd | |
us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
-32500000 | usd | |
CY2022Q2 | us-gaap |
Comprehensive Income Net Of Tax
ComprehensiveIncomeNetOfTax
|
-63700000 | usd |
CY2021Q2 | us-gaap |
Comprehensive Income Net Of Tax
ComprehensiveIncomeNetOfTax
|
59900000 | usd |
us-gaap |
Comprehensive Income Net Of Tax
ComprehensiveIncomeNetOfTax
|
-288100000 | usd | |
us-gaap |
Comprehensive Income Net Of Tax
ComprehensiveIncomeNetOfTax
|
61400000 | usd | |
CY2022Q1 | us-gaap |
Stockholders Equity
StockholdersEquity
|
3441100000 | usd |
CY2022Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
64100000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
-127800000 | usd |
CY2022Q2 | us-gaap |
Stock Repurchased And Retired During Period Shares
StockRepurchasedAndRetiredDuringPeriodShares
|
1722044 | shares |
CY2022Q2 | us-gaap |
Stock Repurchased And Retired During Period Value
StockRepurchasedAndRetiredDuringPeriodValue
|
64500000 | usd |
CY2022Q2 | us-gaap |
Stock Issued During Period Shares New Issues
StockIssuedDuringPeriodSharesNewIssues
|
26266 | shares |
CY2022Q2 | us-gaap |
Stock Issued During Period Value New Issues
StockIssuedDuringPeriodValueNewIssues
|
0 | usd |
CY2022Q2 | us-gaap |
Stock Issued During Period Shares Restricted Stock Award Gross
StockIssuedDuringPeriodSharesRestrictedStockAwardGross
|
2626 | shares |
CY2022Q2 | us-gaap |
Stock Issued During Period Value Share Based Compensation
StockIssuedDuringPeriodValueShareBasedCompensation
|
0 | usd |
CY2022Q2 | us-gaap |
Stock Issued During Period Shares Restricted Stock Award Forfeited
StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited
|
51820 | shares |
CY2022Q2 | us-gaap |
Stock Issued During Period Value Share Based Compensation Forfeited
StockIssuedDuringPeriodValueShareBasedCompensationForfeited
|
0 | usd |
CY2022Q2 | us-gaap |
Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value
AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
|
3800000 | usd |
CY2022Q2 | us-gaap |
Common Stock Dividends Per Share Declared
CommonStockDividendsPerShareDeclared
|
0.41 | |
CY2022Q2 | us-gaap |
Dividends Common Stock Cash
DividendsCommonStockCash
|
44800000 | usd |
CY2022Q2 | us-gaap |
Stockholders Equity
StockholdersEquity
|
3271900000 | usd |
CY2021Q1 | us-gaap |
Stockholders Equity
StockholdersEquity
|
1933400000 | usd |
CY2021Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
42500000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
17400000 | usd |
CY2021Q2 | us-gaap |
Stock Repurchased And Retired During Period Shares
StockRepurchasedAndRetiredDuringPeriodShares
|
284 | shares |
CY2021Q2 | us-gaap |
Stock Repurchased And Retired During Period Value
StockRepurchasedAndRetiredDuringPeriodValue
|
0 | usd |
CY2021Q2 | us-gaap |
Stock Issued During Period Shares New Issues
StockIssuedDuringPeriodSharesNewIssues
|
18477 | shares |
CY2021Q2 | us-gaap |
Stock Issued During Period Value New Issues
StockIssuedDuringPeriodValueNewIssues
|
0 | usd |
CY2021Q2 | us-gaap |
Stock Issued During Period Shares Restricted Stock Award Forfeited
StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited
|
8305 | shares |
CY2021Q2 | us-gaap |
Stock Issued During Period Value Share Based Compensation
StockIssuedDuringPeriodValueShareBasedCompensation
|
0 | usd |
CY2021Q2 | us-gaap |
Stock Issued During Period Value Stock Options Exercised
StockIssuedDuringPeriodValueStockOptionsExercised
|
3100000 | usd |
CY2021Q2 | us-gaap |
Common Stock Dividends Per Share Declared
CommonStockDividendsPerShareDeclared
|
0.41 | |
CY2021Q2 | us-gaap |
Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value
AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
|
-25500000 | usd |
CY2021Q2 | us-gaap |
Stockholders Equity
StockholdersEquity
|
1970900000 | usd |
CY2021Q4 | us-gaap |
Stockholders Equity
StockholdersEquity
|
1986600000 | usd |
us-gaap |
Net Income Loss
NetIncomeLoss
|
30700000 | usd | |
us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
-318800000 | usd | |
us-gaap |
Stock Repurchased And Retired During Period Shares
StockRepurchasedAndRetiredDuringPeriodShares
|
1759742 | shares | |
us-gaap |
Stock Repurchased And Retired During Period Value
StockRepurchasedAndRetiredDuringPeriodValue
|
65900000 | usd | |
us-gaap |
Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent
OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
|
-32500000 | usd | |
us-gaap |
Stock Issued During Period Shares New Issues
StockIssuedDuringPeriodSharesNewIssues
|
46913370 | shares | |
us-gaap |
Stock Issued During Period Value New Issues
StockIssuedDuringPeriodValueNewIssues
|
1722500000 | usd | |
us-gaap |
Stock Issued During Period Shares Restricted Stock Award Gross
StockIssuedDuringPeriodSharesRestrictedStockAwardGross
|
453439 | shares | |
us-gaap |
Stock Issued During Period Value Share Based Compensation
StockIssuedDuringPeriodValueShareBasedCompensation
|
0 | usd | |
us-gaap |
Stock Issued During Period Shares Restricted Stock Award Forfeited
StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited
|
67292 | shares | |
us-gaap |
Stock Issued During Period Value Share Based Compensation Forfeited
StockIssuedDuringPeriodValueShareBasedCompensationForfeited
|
0 | usd | |
us-gaap |
Stock Issued During Period Shares Stock Options Exercised
StockIssuedDuringPeriodSharesStockOptionsExercised
|
17807 | shares | |
fibk |
Shares Tendered In Payment Of Option Price And Income Tax Withholding Amounts Shares
SharesTenderedInPaymentOfOptionPriceAndIncomeTaxWithholdingAmountsShares
|
4877 | shares | |
us-gaap |
Stock Issued During Period Value Stock Options Exercised
StockIssuedDuringPeriodValueStockOptionsExercised
|
100000 | usd | |
us-gaap |
Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value
AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
|
6200000 | usd | |
us-gaap |
Common Stock Dividends Per Share Declared
CommonStockDividendsPerShareDeclared
|
0.82 | ||
us-gaap |
Dividends Common Stock Cash
DividendsCommonStockCash
|
89500000 | usd | |
CY2022Q2 | us-gaap |
Stockholders Equity
StockholdersEquity
|
3271900000 | usd |
CY2020Q4 | us-gaap |
Stockholders Equity
StockholdersEquity
|
1959800000 | usd |
us-gaap |
Net Income Loss
NetIncomeLoss
|
93900000 | usd | |
us-gaap |
Stock Repurchased And Retired During Period Shares
StockRepurchasedAndRetiredDuringPeriodShares
|
127464 | shares | |
us-gaap |
Stock Repurchased And Retired During Period Value
StockRepurchasedAndRetiredDuringPeriodValue
|
5400000 | usd | |
us-gaap |
Stock Issued During Period Shares New Issues
StockIssuedDuringPeriodSharesNewIssues
|
19081 | shares | |
us-gaap |
Stock Issued During Period Value New Issues
StockIssuedDuringPeriodValueNewIssues
|
0 | usd | |
us-gaap |
Stock Issued During Period Shares Restricted Stock Award Gross
StockIssuedDuringPeriodSharesRestrictedStockAwardGross
|
239525 | shares | |
us-gaap |
Stock Issued During Period Value Share Based Compensation
StockIssuedDuringPeriodValueShareBasedCompensation
|
0 | usd | |
us-gaap |
Stock Issued During Period Shares Restricted Stock Award Forfeited
StockIssuedDuringPeriodSharesRestrictedStockAwardForfeited
|
27373 | shares | |
us-gaap |
Stock Issued During Period Value Share Based Compensation Forfeited
StockIssuedDuringPeriodValueShareBasedCompensationForfeited
|
0 | usd | |
us-gaap |
Stock Issued During Period Shares Stock Options Exercised
StockIssuedDuringPeriodSharesStockOptionsExercised
|
40663 | shares | |
fibk |
Shares Tendered In Payment Of Option Price And Income Tax Withholding Amounts Shares
SharesTenderedInPaymentOfOptionPriceAndIncomeTaxWithholdingAmountsShares
|
6177 | shares | |
us-gaap |
Stock Issued During Period Value Stock Options Exercised
StockIssuedDuringPeriodValueStockOptionsExercised
|
400000 | usd | |
us-gaap |
Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value
AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
|
5500000 | usd | |
us-gaap |
Common Stock Dividends Per Share Declared
CommonStockDividendsPerShareDeclared
|
0.82 | ||
us-gaap |
Dividends Common Stock Cash
DividendsCommonStockCash
|
50800000 | usd | |
CY2021Q2 | us-gaap |
Stockholders Equity
StockholdersEquity
|
1970900000 | usd |
us-gaap |
Net Income Loss
NetIncomeLoss
|
30700000 | usd | |
us-gaap |
Net Income Loss
NetIncomeLoss
|
93900000 | usd | |
us-gaap |
Provision For Loan And Lease Losses
ProvisionForLoanAndLeaseLosses
|
59600000 | usd | |
us-gaap |
Provision For Loan And Lease Losses
ProvisionForLoanAndLeaseLosses
|
-5100000 | usd | |
us-gaap |
Gain Loss On Sale Of Property Plant Equipment
GainLossOnSaleOfPropertyPlantEquipment
|
1400000 | usd | |
us-gaap |
Gain Loss On Sale Of Property Plant Equipment
GainLossOnSaleOfPropertyPlantEquipment
|
400000 | usd | |
us-gaap |
Depreciation Depletion And Amortization
DepreciationDepletionAndAmortization
|
27500000 | usd | |
us-gaap |
Depreciation Depletion And Amortization
DepreciationDepletionAndAmortization
|
22300000 | usd | |
us-gaap |
Accretion Amortization Of Discounts And Premiums Investments
AccretionAmortizationOfDiscountsAndPremiumsInvestments
|
-13500000 | usd | |
us-gaap |
Accretion Amortization Of Discounts And Premiums Investments
AccretionAmortizationOfDiscountsAndPremiumsInvestments
|
-18300000 | usd | |
us-gaap |
Debt And Equity Securities Gain Loss
DebtAndEquitySecuritiesGainLoss
|
-200000 | usd | |
us-gaap |
Debt And Equity Securities Gain Loss
DebtAndEquitySecuritiesGainLoss
|
-100000 | usd | |
us-gaap |
Gain Loss On Sale Of Loans And Leases
GainLossOnSaleOfLoansAndLeases
|
7600000 | usd | |
us-gaap |
Gain Loss On Sale Of Loans And Leases
GainLossOnSaleOfLoansAndLeases
|
10700000 | usd | |
us-gaap |
Gains Losses On Sales Of Other Real Estate
GainsLossesOnSalesOfOtherRealEstate
|
100000 | usd | |
us-gaap |
Gains Losses On Sales Of Other Real Estate
GainsLossesOnSalesOfOtherRealEstate
|
200000 | usd | |
us-gaap |
Gains Losses On Extinguishment Of Debt
GainsLossesOnExtinguishmentOfDebt
|
1400000 | usd | |
us-gaap |
Gains Losses On Extinguishment Of Debt
GainsLossesOnExtinguishmentOfDebt
|
0 | usd | |
us-gaap |
Mortgage Servicing Rights Msr Impairment Recovery
MortgageServicingRightsMSRImpairmentRecovery
|
-3400000 | usd | |
us-gaap |
Mortgage Servicing Rights Msr Impairment Recovery
MortgageServicingRightsMSRImpairmentRecovery
|
-5900000 | usd | |
us-gaap |
Deferred Income Tax Expense Benefit
DeferredIncomeTaxExpenseBenefit
|
-8800000 | usd | |
us-gaap |
Deferred Income Tax Expense Benefit
DeferredIncomeTaxExpenseBenefit
|
9000000.0 | usd | |
us-gaap |
Life Insurance Corporate Or Bank Owned Change In Value
LifeInsuranceCorporateOrBankOwnedChangeInValue
|
4700000 | usd | |
us-gaap |
Life Insurance Corporate Or Bank Owned Change In Value
LifeInsuranceCorporateOrBankOwnedChangeInValue
|
2600000 | usd | |
us-gaap |
Share Based Compensation
ShareBasedCompensation
|
6200000 | usd | |
us-gaap |
Share Based Compensation
ShareBasedCompensation
|
5500000 | usd | |
us-gaap |
Payments For Origination Of Mortgage Loans Held For Sale
PaymentsForOriginationOfMortgageLoansHeldForSale
|
241200000 | usd | |
us-gaap |
Payments For Origination Of Mortgage Loans Held For Sale
PaymentsForOriginationOfMortgageLoansHeldForSale
|
359300000 | usd | |
us-gaap |
Proceeds From Sale Of Mortgage Loans Held For Sale
ProceedsFromSaleOfMortgageLoansHeldForSale
|
263100000 | usd | |
us-gaap |
Proceeds From Sale Of Mortgage Loans Held For Sale
ProceedsFromSaleOfMortgageLoansHeldForSale
|
394300000 | usd | |
us-gaap |
Increase Decrease In Accrued Interest Receivable Net
IncreaseDecreaseInAccruedInterestReceivableNet
|
10100000 | usd | |
us-gaap |
Increase Decrease In Accrued Interest Receivable Net
IncreaseDecreaseInAccruedInterestReceivableNet
|
-200000 | usd | |
us-gaap |
Increase Decrease In Other Operating Assets
IncreaseDecreaseInOtherOperatingAssets
|
-7600000 | usd | |
us-gaap |
Increase Decrease In Other Operating Assets
IncreaseDecreaseInOtherOperatingAssets
|
39300000 | usd | |
us-gaap |
Increase Decrease In Interest Payable Net
IncreaseDecreaseInInterestPayableNet
|
-1800000 | usd | |
us-gaap |
Increase Decrease In Interest Payable Net
IncreaseDecreaseInInterestPayableNet
|
-800000 | usd | |
us-gaap |
Increase Decrease In Accounts Payable And Accrued Liabilities
IncreaseDecreaseInAccountsPayableAndAccruedLiabilities
|
141300000 | usd | |
us-gaap |
Increase Decrease In Accounts Payable And Accrued Liabilities
IncreaseDecreaseInAccountsPayableAndAccruedLiabilities
|
-13200000 | usd | |
us-gaap |
Net Cash Provided By Used In Operating Activities
NetCashProvidedByUsedInOperatingActivities
|
269200000 | usd | |
us-gaap |
Net Cash Provided By Used In Operating Activities
NetCashProvidedByUsedInOperatingActivities
|
106100000 | usd | |
us-gaap |
Payments To Acquire Held To Maturity Securities
PaymentsToAcquireHeldToMaturitySecurities
|
848200000 | usd | |
us-gaap |
Payments To Acquire Held To Maturity Securities
PaymentsToAcquireHeldToMaturitySecurities
|
1022100000 | usd | |
us-gaap |
Payments To Acquire Available For Sale Securities Debt
PaymentsToAcquireAvailableForSaleSecuritiesDebt
|
2521200000 | usd | |
us-gaap |
Payments To Acquire Available For Sale Securities Debt
PaymentsToAcquireAvailableForSaleSecuritiesDebt
|
1219900000 | usd | |
us-gaap |
Proceeds From Sale And Maturity Of Held To Maturity Securities
ProceedsFromSaleAndMaturityOfHeldToMaturitySecurities
|
193400000 | usd | |
us-gaap |
Proceeds From Sale And Maturity Of Held To Maturity Securities
ProceedsFromSaleAndMaturityOfHeldToMaturitySecurities
|
55400000 | usd | |
us-gaap |
Proceeds From Sale And Maturity Of Available For Sale Securities
ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities
|
1057800000 | usd | |
us-gaap |
Proceeds From Sale And Maturity Of Available For Sale Securities
ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities
|
542500000 | usd | |
us-gaap |
Payments For Proceeds From Other Loans And Leases
PaymentsForProceedsFromOtherLoansAndLeases
|
39200000 | usd | |
us-gaap |
Payments For Proceeds From Other Loans And Leases
PaymentsForProceedsFromOtherLoansAndLeases
|
37000000.0 | usd | |
fibk |
Payments For Proceeds From Recoveriesof Loans Previously Chargedoff
PaymentsForProceedsFromRecoveriesofLoansPreviouslyChargedoff
|
0 | usd | |
fibk |
Payments For Proceeds From Recoveriesof Loans Previously Chargedoff
PaymentsForProceedsFromRecoveriesofLoansPreviouslyChargedoff
|
-5700000 | usd | |
us-gaap |
Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans
ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans
|
1200000 | usd | |
us-gaap |
Proceeds From Sale Of Wholly Owned Real Estate And Real Estate Acquired In Settlement Of Loans
ProceedsFromSaleOfWhollyOwnedRealEstateAndRealEstateAcquiredInSettlementOfLoans
|
1000000.0 | usd | |
fibk |
Proceeds From The Sale Of Health Savings Accounts
ProceedsFromTheSaleOfHealthSavingsAccounts
|
1400000 | usd | |
fibk |
Proceeds From The Sale Of Health Savings Accounts
ProceedsFromTheSaleOfHealthSavingsAccounts
|
0 | usd | |
us-gaap |
Cash Acquired From Acquisition
CashAcquiredFromAcquisition
|
2006900000 | usd | |
us-gaap |
Cash Acquired From Acquisition
CashAcquiredFromAcquisition
|
0 | usd | |
us-gaap |
Payments For Proceeds From Productive Assets
PaymentsForProceedsFromProductiveAssets
|
15500000 | usd | |
us-gaap |
Payments For Proceeds From Productive Assets
PaymentsForProceedsFromProductiveAssets
|
300000 | usd | |
us-gaap |
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInInvestingActivities
|
-163400000 | usd | |
us-gaap |
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInInvestingActivities
|
-1674700000 | usd | |
us-gaap |
Increase Decrease In Deposits
IncreaseDecreaseInDeposits
|
-1093800000 | usd | |
us-gaap |
Increase Decrease In Deposits
IncreaseDecreaseInDeposits
|
1348700000 | usd | |
us-gaap |
Proceeds From Payments For In Securities Sold Under Agreements To Repurchase
ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase
|
8500000 | usd | |
us-gaap |
Proceeds From Payments For In Securities Sold Under Agreements To Repurchase
ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase
|
-52700000 | usd | |
CY2021Q4 | us-gaap |
Long Term Accounts Notes And Loans Receivable Net Noncurrent
LongTermAccountsNotesAndLoansReceivableNetNoncurrent
|
100000 | usd |
us-gaap |
Repayments Of Other Long Term Debt
RepaymentsOfOtherLongTermDebt
|
157900000 | usd | |
us-gaap |
Repayments Of Other Long Term Debt
RepaymentsOfOtherLongTermDebt
|
0 | usd | |
us-gaap |
Proceeds From Issuance Of Unsecured Debt
ProceedsFromIssuanceOfUnsecuredDebt
|
8000000.0 | usd | |
us-gaap |
Proceeds From Issuance Of Unsecured Debt
ProceedsFromIssuanceOfUnsecuredDebt
|
0 | usd | |
us-gaap |
Payments Of Stock Issuance Costs
PaymentsOfStockIssuanceCosts
|
800000 | usd | |
us-gaap |
Payments Of Stock Issuance Costs
PaymentsOfStockIssuanceCosts
|
0 | usd | |
us-gaap |
Proceeds From Issuance Of Common Stock
ProceedsFromIssuanceOfCommonStock
|
100000 | usd | |
us-gaap |
Proceeds From Issuance Of Common Stock
ProceedsFromIssuanceOfCommonStock
|
400000 | usd | |
us-gaap |
Payments For Repurchase Of Common Stock
PaymentsForRepurchaseOfCommonStock
|
65900000 | usd | |
us-gaap |
Payments For Repurchase Of Common Stock
PaymentsForRepurchaseOfCommonStock
|
5400000 | usd | |
us-gaap |
Payments Of Dividends Common Stock
PaymentsOfDividendsCommonStock
|
89500000 | usd | |
us-gaap |
Payments Of Dividends Common Stock
PaymentsOfDividendsCommonStock
|
50800000 | usd | |
us-gaap |
Net Cash Provided By Used In Financing Activities
NetCashProvidedByUsedInFinancingActivities
|
-1391300000 | usd | |
us-gaap |
Net Cash Provided By Used In Financing Activities
NetCashProvidedByUsedInFinancingActivities
|
1240200000 | usd | |
us-gaap |
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
|
-1285500000 | usd | |
us-gaap |
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
|
-328400000 | usd | |
CY2021Q4 | us-gaap |
Loans And Leases Receivable Impaired Commitment To Lend
LoansAndLeasesReceivableImpairedCommitmentToLend
|
0 | usd |
CY2021Q4 | us-gaap |
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
|
2344800000 | usd |
CY2020Q4 | us-gaap |
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
|
2276800000 | usd |
CY2022Q2 | us-gaap |
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
|
1059300000 | usd |
CY2021Q2 | us-gaap |
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents
CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents
|
1948400000 | usd |
us-gaap |
Income Taxes Paid
IncomeTaxesPaid
|
13800000 | usd | |
us-gaap |
Income Taxes Paid
IncomeTaxesPaid
|
35700000 | usd | |
us-gaap |
Interest Paid Net
InterestPaidNet
|
13500000 | usd | |
us-gaap |
Interest Paid Net
InterestPaidNet
|
9800000 | usd | |
us-gaap |
Finance Lease Right Of Use Asset Amortization
FinanceLeaseRightOfUseAssetAmortization
|
19900000 | usd | |
us-gaap |
Finance Lease Right Of Use Asset Amortization
FinanceLeaseRightOfUseAssetAmortization
|
400000 | usd | |
us-gaap |
Held To Maturity Securities Transferred Security Unrealized Gain Loss
HeldToMaturitySecuritiesTransferredSecurityUnrealizedGainLoss
|
10900000 | usd | |
us-gaap |
Held To Maturity Securities Transferred Security Unrealized Gain Loss
HeldToMaturitySecuritiesTransferredSecurityUnrealizedGainLoss
|
0 | usd | |
fibk |
Debt Securities Available For Sale Transfer Unrealized Gain Loss
DebtSecuritiesAvailableForSaleTransferUnrealizedGainLoss
|
463600000 | usd | |
fibk |
Debt Securities Available For Sale Transfer Unrealized Gain Loss
DebtSecuritiesAvailableForSaleTransferUnrealizedGainLoss
|
672200000 | usd | |
us-gaap |
Transfer Of Loans Held For Sale To Portfolio Loans1
TransferOfLoansHeldForSaleToPortfolioLoans1
|
19800000 | usd | |
us-gaap |
Transfer Of Loans Held For Sale To Portfolio Loans1
TransferOfLoansHeldForSaleToPortfolioLoans1
|
0 | usd | |
us-gaap |
Transfer To Other Real Estate
TransferToOtherRealEstate
|
100000 | usd | |
us-gaap |
Transfer To Other Real Estate
TransferToOtherRealEstate
|
300000 | usd | |
us-gaap |
Asset Acquisition Consideration Transferred Equity Interest Issued And Issuable
AssetAcquisitionConsiderationTransferredEquityInterestIssuedAndIssuable
|
1723300000 | usd | |
us-gaap |
Asset Acquisition Consideration Transferred Equity Interest Issued And Issuable
AssetAcquisitionConsiderationTransferredEquityInterestIssuedAndIssuable
|
0 | usd | |
fibk |
Capitalization Of Internally Originated Mortgage Servicing Rights Noncash Supplemental Disclosures
CapitalizationOfInternallyOriginatedMortgageServicingRightsNoncashSupplementalDisclosures
|
1600000 | usd | |
fibk |
Capitalization Of Internally Originated Mortgage Servicing Rights Noncash Supplemental Disclosures
CapitalizationOfInternallyOriginatedMortgageServicingRightsNoncashSupplementalDisclosures
|
900000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Investments Acquired1
NoncashOrPartNoncashAcquisitionInvestmentsAcquired1
|
2699000000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Investments Acquired1
NoncashOrPartNoncashAcquisitionInvestmentsAcquired1
|
0 | usd | |
us-gaap |
Securities Purchased Under Agreements To Resell Increase
SecuritiesPurchasedUnderAgreementsToResellIncrease
|
101100000 | usd | |
us-gaap |
Securities Purchased Under Agreements To Resell Increase
SecuritiesPurchasedUnderAgreementsToResellIncrease
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Loans Held For Sale Acquired
NoncashOrPartNoncashAcquisitionLoansHeldForSaleAcquired
|
217000000.0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Loans Held For Sale Acquired
NoncashOrPartNoncashAcquisitionLoansHeldForSaleAcquired
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Loans Acquired
NoncashOrPartNoncashAcquisitionLoansAcquired
|
7645500000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Loans Acquired
NoncashOrPartNoncashAcquisitionLoansAcquired
|
0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Fixed Assets Acquired1
NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1
|
144900000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Fixed Assets Acquired1
NoncashOrPartNoncashAcquisitionFixedAssetsAcquired1
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Goodwill
NoncashOrPartNoncashAcquisitionGoodwill
|
478200000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Goodwill
NoncashOrPartNoncashAcquisitionGoodwill
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Company Owned Life Insurance Acquired
NoncashOrPartNoncashAcquisitionCompanyOwnedLifeInsuranceAcquired
|
186600000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Company Owned Life Insurance Acquired
NoncashOrPartNoncashAcquisitionCompanyOwnedLifeInsuranceAcquired
|
0 | usd | |
us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
7700000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Deferred Tax Assets Acquired
NoncashOrPartNoncashAcquisitionDeferredTaxAssetsAcquired
|
63600000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Deferred Tax Assets Acquired
NoncashOrPartNoncashAcquisitionDeferredTaxAssetsAcquired
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Assets Acquired Other Real Estate Owned
NoncashOrPartNoncashAcquisitionAssetsAcquiredOtherRealEstateOwned
|
15800000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Assets Acquired Other Real Estate Owned
NoncashOrPartNoncashAcquisitionAssetsAcquiredOtherRealEstateOwned
|
0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Other Assets Acquired1
NoncashOrPartNoncashAcquisitionOtherAssetsAcquired1
|
198000000.0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Other Assets Acquired1
NoncashOrPartNoncashAcquisitionOtherAssetsAcquired1
|
0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Value Of Assets Acquired1
NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1
|
11823900000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Value Of Assets Acquired1
NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Liabilities Assumed Deposits
NoncashOrPartNoncashAcquisitionLiabilitiesAssumedDeposits
|
11688000000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Liabilities Assumed Deposits
NoncashOrPartNoncashAcquisitionLiabilitiesAssumedDeposits
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Securities Sold Under Repurchase Agreements
NoncashOrPartNoncashAcquisitionSecuritiesSoldUnderRepurchaseAgreements
|
74000000.0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Securities Sold Under Repurchase Agreements
NoncashOrPartNoncashAcquisitionSecuritiesSoldUnderRepurchaseAgreements
|
0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Payables Assumed1
NoncashOrPartNoncashAcquisitionPayablesAssumed1
|
110100000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Payables Assumed1
NoncashOrPartNoncashAcquisitionPayablesAssumed1
|
0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Debt Assumed1
NoncashOrPartNoncashAcquisitionDebtAssumed1
|
159300000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Debt Assumed1
NoncashOrPartNoncashAcquisitionDebtAssumed1
|
0 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Liabilities Assumed Trust Preferred Securities
NoncashOrPartNoncashAcquisitionLiabilitiesAssumedTrustPreferredSecurities
|
76100000 | usd | |
fibk |
Noncash Or Part Noncash Acquisition Liabilities Assumed Trust Preferred Securities
NoncashOrPartNoncashAcquisitionLiabilitiesAssumedTrustPreferredSecurities
|
0 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1
NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1
|
12107500000 | usd | |
us-gaap |
Noncash Or Part Noncash Acquisition Value Of Liabilities Assumed1
NoncashOrPartNoncashAcquisitionValueOfLiabilitiesAssumed1
|
0 | usd | |
CY2022Q2 | us-gaap |
Goodwill Period Increase Decrease
GoodwillPeriodIncreaseDecrease
|
-37800000 | usd |
CY2022Q2 | us-gaap |
Goodwill Period Increase Decrease
GoodwillPeriodIncreaseDecrease
|
-37800000 | usd |
CY2022Q2 | us-gaap |
Business Combination Acquisition Related Costs
BusinessCombinationAcquisitionRelatedCosts
|
45800000 | usd |
CY2022Q2 | us-gaap |
Business Acquisition Pro Forma Earnings Per Share Basic
BusinessAcquisitionProFormaEarningsPerShareBasic
|
0.93 | |
CY2021Q2 | us-gaap |
Business Acquisition Pro Forma Earnings Per Share Basic
BusinessAcquisitionProFormaEarningsPerShareBasic
|
1.33 | |
us-gaap |
Business Acquisition Pro Forma Earnings Per Share Basic
BusinessAcquisitionProFormaEarningsPerShareBasic
|
1.76 | ||
us-gaap |
Business Acquisition Pro Forma Earnings Per Share Basic
BusinessAcquisitionProFormaEarningsPerShareBasic
|
0.61 | ||
CY2022Q2 | us-gaap |
Business Acquisition Pro Forma Earnings Per Share Diluted
BusinessAcquisitionProFormaEarningsPerShareDiluted
|
0.93 | |
CY2021Q2 | us-gaap |
Business Acquisition Pro Forma Earnings Per Share Diluted
BusinessAcquisitionProFormaEarningsPerShareDiluted
|
1.33 | |
us-gaap |
Business Acquisition Pro Forma Earnings Per Share Diluted
BusinessAcquisitionProFormaEarningsPerShareDiluted
|
1.76 | ||
us-gaap |
Business Acquisition Pro Forma Earnings Per Share Diluted
BusinessAcquisitionProFormaEarningsPerShareDiluted
|
0.61 | ||
us-gaap |
Goodwill Impairment Loss
GoodwillImpairmentLoss
|
0 | usd | |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Accumulated Amortization
FiniteLivedIntangibleAssetsAccumulatedAmortization
|
72400000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Net
FiniteLivedIntangibleAssetsNet
|
105100000 | usd |
CY2021Q4 | us-gaap |
Goodwill
Goodwill
|
621600000 | usd |
us-gaap |
Amortization Of Intangible Assets
AmortizationOfIntangibleAssets
|
5000000 | usd | |
CY2020Q4 | us-gaap |
Goodwill
Goodwill
|
621600000 | usd |
us-gaap |
Goodwill Acquired During Period
GoodwillAcquiredDuringPeriod
|
478200000 | usd | |
CY2021 | us-gaap |
Goodwill Acquired During Period
GoodwillAcquiredDuringPeriod
|
0 | usd |
CY2022Q2 | us-gaap |
Goodwill
Goodwill
|
1099800000 | usd |
CY2021Q4 | us-gaap |
Goodwill
Goodwill
|
621600000 | usd |
CY2021Q4 | us-gaap |
Finite Lived Intangible Assets Gross
FiniteLivedIntangibleAssetsGross
|
106000000.0 | usd |
us-gaap |
Finitelived Intangible Assets Acquired1
FinitelivedIntangibleAssetsAcquired1
|
72900000 | usd | |
us-gaap |
Finite Lived Intangible Assets Period Increase Decrease
FiniteLivedIntangibleAssetsPeriodIncreaseDecrease
|
-1400000 | usd | |
CY2020Q4 | us-gaap |
Finite Lived Intangible Assets Gross
FiniteLivedIntangibleAssetsGross
|
106000000.0 | usd |
CY2021Q4 | us-gaap |
Finite Lived Intangible Assets Accumulated Amortization
FiniteLivedIntangibleAssetsAccumulatedAmortization
|
64700000 | usd |
CY2021Q4 | us-gaap |
Finite Lived Intangible Assets Net
FiniteLivedIntangibleAssetsNet
|
41300000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Amortization Expense Remainder Of Fiscal Year
FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear
|
8100000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Amortization Expense Next Twelve Months
FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
|
15600000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Amortization Expense Year Two
FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
|
14600000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Amortization Expense Year Three
FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
|
13700000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Amortization Expense Year Four
FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
|
12800000 | usd |
CY2022Q2 | fibk |
Finite Lived Intangible Asset Expected Amortization After Year Four
FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour
|
40300000 | usd |
CY2022Q2 | us-gaap |
Finite Lived Intangible Assets Net
FiniteLivedIntangibleAssetsNet
|
105100000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Debt Securities Amortized Cost Basis
AvailableForSaleDebtSecuritiesAmortizedCostBasis
|
8193800000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax
AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
|
3500000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax
AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
|
456200000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Securities
AvailableForSaleSecuritiesDebtSecurities
|
7741100000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities
HeldToMaturitySecurities
|
3131600000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
1600000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Held To Maturity Amortized Cost After Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss
|
3130000000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Accumulated Unrecognized Holding Gain
HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain
|
500000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Accumulated Unrecognized Holding Loss
HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
|
270000000.0 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Fair Value
HeldToMaturitySecuritiesFairValue
|
2860500000 | usd |
CY2021Q4 | us-gaap |
Available For Sale Debt Securities Amortized Cost Basis
AvailableForSaleDebtSecuritiesAmortizedCostBasis
|
4859300000 | usd |
CY2021Q4 | us-gaap |
Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax
AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
|
20600000 | usd |
CY2021Q4 | us-gaap |
Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax
AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
|
59400000 | usd |
CY2021Q4 | us-gaap |
Available For Sale Securities Debt Securities
AvailableForSaleSecuritiesDebtSecurities
|
4820500000 | usd |
CY2021Q4 | us-gaap |
Held To Maturity Securities
HeldToMaturitySecurities
|
1687600000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2021Q4 | us-gaap |
Debt Securities Held To Maturity Amortized Cost After Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss
|
1687600000 | usd |
CY2021Q4 | us-gaap |
Held To Maturity Securities Accumulated Unrecognized Holding Gain
HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain
|
15600000 | usd |
CY2021Q4 | us-gaap |
Held To Maturity Securities Accumulated Unrecognized Holding Loss
HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
|
35700000 | usd |
CY2021Q4 | us-gaap |
Held To Maturity Securities Fair Value
HeldToMaturitySecuritiesFairValue
|
1667500000 | usd |
CY2022Q1 | us-gaap |
Debt Securities Held To Maturity Transfer Amount
DebtSecuritiesHeldToMaturityTransferAmount
|
10700000 | usd |
CY2022Q1 | fibk |
Debt Securities Held To Maturity After Allowance For Credit Loss Transfer Amount
DebtSecuritiesHeldToMaturityAfterAllowanceForCreditLossTransferAmount
|
10900000 | usd |
CY2022Q1 | fibk |
Debt Securities Available For Sale Amortized Cost After Allowance For Credit Loss Transfer Amount
DebtSecuritiesAvailableForSaleAmortizedCostAfterAllowanceForCreditLossTransferAmount
|
485900000 | usd |
CY2022Q1 | fibk |
Debt Securities Available For Sale After Allowance For Credit Loss Transfer Amount
DebtSecuritiesAvailableForSaleAfterAllowanceForCreditLossTransferAmount
|
463600000 | usd |
CY2022Q1 | us-gaap |
Held To Maturity Securities Transferred To Trading Securities Unrealized Gain Loss
HeldToMaturitySecuritiesTransferredToTradingSecuritiesUnrealizedGainLoss
|
0 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
|
5830500000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
|
287100000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger
|
1331900000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
|
169100000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Unrealized Loss Position
DebtSecuritiesAvailableForSaleUnrealizedLossPosition
|
7162400000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss
DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
|
456200000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
|
2760300000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
|
58300000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger
|
68700000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss
DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
|
1100000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Unrealized Loss Position
DebtSecuritiesAvailableForSaleUnrealizedLossPosition
|
2829000000 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss
DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
|
59400000 | usd |
CY2022Q2 | us-gaap |
Debt Securities Available For Sale Allowance For Credit Loss
DebtSecuritiesAvailableForSaleAllowanceForCreditLoss
|
0 | usd |
CY2021Q4 | us-gaap |
Debt Securities Available For Sale Allowance For Credit Loss
DebtSecuritiesAvailableForSaleAllowanceForCreditLoss
|
0 | usd |
CY2022Q2 | fibk |
Available For Sale And Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions
AvailableForSaleAndHeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions
|
1155 | investments |
CY2021Q4 | fibk |
Available For Sale And Held To Maturity Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions
AvailableForSaleAndHeldToMaturitySecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions
|
285 | investments |
CY2022Q1 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
1600000 | usd |
us-gaap |
Debt Securities Available For Sale Realized Loss
DebtSecuritiesAvailableForSaleRealizedLoss
|
0 | usd | |
CY2021Q1 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2021Q4 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2020Q4 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2022Q2 | us-gaap |
Debt Securities Held To Maturity Credit Loss Expense Reversal
DebtSecuritiesHeldToMaturityCreditLossExpenseReversal
|
0 | usd |
CY2021Q2 | us-gaap |
Debt Securities Held To Maturity Credit Loss Expense Reversal
DebtSecuritiesHeldToMaturityCreditLossExpenseReversal
|
0 | usd |
us-gaap |
Debt Securities Held To Maturity Credit Loss Expense Reversal
DebtSecuritiesHeldToMaturityCreditLossExpenseReversal
|
1600000 | usd | |
us-gaap |
Debt Securities Held To Maturity Credit Loss Expense Reversal
DebtSecuritiesHeldToMaturityCreditLossExpenseReversal
|
0 | usd | |
CY2022Q2 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
1600000 | usd |
CY2021Q2 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2022Q2 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
1600000 | usd |
CY2021Q2 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2021Q4 | us-gaap |
Debt Securities Held To Maturity Allowance For Credit Loss
DebtSecuritiesHeldToMaturityAllowanceForCreditLoss
|
0 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities
HeldToMaturitySecurities
|
3131600000 | usd |
CY2021Q4 | us-gaap |
Held To Maturity Securities
HeldToMaturitySecurities
|
1687600000 | usd |
us-gaap |
Debt Securities Available For Sale Realized Gain
DebtSecuritiesAvailableForSaleRealizedGain
|
0 | usd | |
us-gaap |
Debt Securities Available For Sale Realized Gain
DebtSecuritiesAvailableForSaleRealizedGain
|
0 | usd | |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Next Rolling Twelve Months Amortized Cost Basis
AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis
|
84800000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Next Rolling Twelve Months Fair Value
AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue
|
84400000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount
HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount
|
10100000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities Next Rolling Twelve Months Fair Value
HeldToMaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue
|
10100000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Rolling Year Two Through Five Amortized Cost Basis
AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis
|
1566400000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Rolling Year Two Through Five Fair Value
AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue
|
1507700000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount
HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount
|
375000000.0 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities Rolling Year Two Through Five Fair Value
HeldToMaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue
|
367900000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Amortized Cost Basis
AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis
|
1865400000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Rolling Year Six Through Ten Fair Value
AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue
|
1738600000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount
HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount
|
784500000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities Rolling Year Six Through Ten Fair Value
HeldToMaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue
|
718400000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Rolling After Year Ten Amortized Cost Basis
AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis
|
4677200000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Maturities Rolling After Year Ten Fair Value
AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue
|
4410400000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount
HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount
|
1962000000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Debt Maturities Rolling After Ten Years Fair Value
HeldToMaturitySecuritiesDebtMaturitiesRollingAfterTenYearsFairValue
|
1764100000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Debt Securities Amortized Cost Basis
AvailableForSaleDebtSecuritiesAmortizedCostBasis
|
8193800000 | usd |
CY2022Q2 | us-gaap |
Available For Sale Securities Debt Securities
AvailableForSaleSecuritiesDebtSecurities
|
7741100000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities
HeldToMaturitySecurities
|
3131600000 | usd |
CY2022Q2 | us-gaap |
Held To Maturity Securities Fair Value
HeldToMaturitySecuritiesFairValue
|
2860500000 | usd |
CY2022Q2 | us-gaap |
Securities Sold Under Agreements To Repurchase Fair Value Of Collateral
SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral
|
4871300000 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase Fair Value Of Collateral
SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral
|
2617800000 | usd |
CY2022Q2 | us-gaap |
Securities Loaned Or Sold Under Agreements To Repurchase Fair Value Disclosure
SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure
|
4526500000 | usd |
CY2021Q4 | us-gaap |
Securities Loaned Or Sold Under Agreements To Repurchase Fair Value Disclosure
SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure
|
2610800000 | usd |
CY2022Q1 | us-gaap |
Proceeds From Collection Of Loans Held For Sale
ProceedsFromCollectionOfLoansHeldForSale
|
4500000 | usd |
CY2022Q2 | us-gaap |
Proceeds From Collection Of Loans Held For Sale
ProceedsFromCollectionOfLoansHeldForSale
|
53900000 | usd |
CY2022Q2 | us-gaap |
Loans And Leases Receivable Deferred Income
LoansAndLeasesReceivableDeferredIncome
|
10600000 | usd |
CY2021Q4 | us-gaap |
Loans And Leases Receivable Deferred Income
LoansAndLeasesReceivableDeferredIncome
|
12300000 | usd |
CY2022Q2 | us-gaap |
Loans And Leases Receivable Net Of Deferred Income
LoansAndLeasesReceivableNetOfDeferredIncome
|
17162500000 | usd |
CY2021Q4 | us-gaap |
Loans And Leases Receivable Net Of Deferred Income
LoansAndLeasesReceivableNetOfDeferredIncome
|
9331700000 | usd |
CY2022Q2 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
220400000 | usd |
CY2021Q4 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
122300000 | usd |
CY2022Q2 | us-gaap |
Loans And Leases Receivable Net Reported Amount
LoansAndLeasesReceivableNetReportedAmount
|
16942100000 | usd |
CY2021Q4 | us-gaap |
Loans And Leases Receivable Net Reported Amount
LoansAndLeasesReceivableNetReportedAmount
|
9209400000 | usd |
CY2022Q1 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
247200000 | usd |
CY2022Q2 | us-gaap |
Financing Receivable Purchased With Credit Deterioration Allowance For Credit Loss At Acquisition Date
FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate
|
-24800000 | usd |
CY2022Q2 | us-gaap |
Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal
OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal
|
-1700000 | usd |
CY2022Q2 | us-gaap |
Allowance For Loan And Lease Losses Write Offs
AllowanceForLoanAndLeaseLossesWriteOffs
|
3700000 | usd |
CY2022Q2 | us-gaap |
Financing Receivable Allowance For Credit Losses Recovery
FinancingReceivableAllowanceForCreditLossesRecovery
|
3400000 | usd |
CY2022Q2 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
220400000 | usd |
CY2021Q4 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
122300000 | usd |
us-gaap |
Financing Receivable Purchased With Credit Deterioration Allowance For Credit Loss At Acquisition Date
FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate
|
59500000 | usd | |
us-gaap |
Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal
OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal
|
55600000 | usd | |
us-gaap |
Allowance For Loan And Lease Losses Write Offs
AllowanceForLoanAndLeaseLossesWriteOffs
|
23600000 | usd | |
us-gaap |
Financing Receivable Allowance For Credit Losses Recovery
FinancingReceivableAllowanceForCreditLossesRecovery
|
6600000 | usd | |
CY2022Q2 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
220400000 | usd |
CY2021Q1 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
136600000 | usd |
CY2021Q2 | us-gaap |
Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal
OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal
|
0 | usd |
CY2021Q2 | us-gaap |
Allowance For Loan And Lease Losses Write Offs
AllowanceForLoanAndLeaseLossesWriteOffs
|
4800000 | usd |
CY2021Q2 | us-gaap |
Financing Receivable Allowance For Credit Losses Recovery
FinancingReceivableAllowanceForCreditLossesRecovery
|
3700000 | usd |
CY2021Q2 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
135500000 | usd |
CY2020Q4 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
144300000 | usd |
us-gaap |
Off Balance Sheet Credit Loss Liability Credit Loss Expense Reversal
OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal
|
-4800000 | usd | |
us-gaap |
Allowance For Loan And Lease Losses Write Offs
AllowanceForLoanAndLeaseLossesWriteOffs
|
9700000 | usd | |
us-gaap |
Financing Receivable Allowance For Credit Losses Recovery
FinancingReceivableAllowanceForCreditLossesRecovery
|
5700000 | usd | |
CY2021Q2 | us-gaap |
Allowance For Doubtful Accounts Receivable
AllowanceForDoubtfulAccountsReceivable
|
135500000 | usd |
CY2022Q2 | us-gaap |
Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss
FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
|
85500000 | usd |
CY2021Q4 | us-gaap |
Financing Receivable Excluding Accrued Interest Before Allowance For Credit Loss
FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
|
11700000 | usd |
CY2022Q1 | us-gaap |
Financing Receivable Nonaccrual Interest Income
FinancingReceivableNonaccrualInterestIncome
|
0 | usd |
CY2022Q2 | us-gaap |
Financing Receivable Nonaccrual Interest Income
FinancingReceivableNonaccrualInterestIncome
|
0 | usd |
CY2022Q2 | us-gaap |
Impaired Financing Receivable Interest Income Accrual Method
ImpairedFinancingReceivableInterestIncomeAccrualMethod
|
0 | usd |
CY2021Q2 | us-gaap |
Impaired Financing Receivable Interest Income Accrual Method
ImpairedFinancingReceivableInterestIncomeAccrualMethod
|
0 | usd |
us-gaap |
Impaired Financing Receivable Interest Income Accrual Method
ImpairedFinancingReceivableInterestIncomeAccrualMethod
|
0 | usd | |
us-gaap |
Impaired Financing Receivable Interest Income Accrual Method
ImpairedFinancingReceivableInterestIncomeAccrualMethod
|
0 | usd | |
us-gaap |
Financing Receivable Accrued Interest Writeoff
FinancingReceivableAccruedInterestWriteoff
|
0 | usd | |
CY2022Q2 | us-gaap |
Financing Receivable Modifications Recorded Investment
FinancingReceivableModificationsRecordedInvestment
|
28900000 | usd |
CY2022Q2 | fibk |
Financing Receivable Modifications Recorded Investment Non Accrual
FinancingReceivableModificationsRecordedInvestmentNonAccrual
|
8400000 | usd |
CY2022Q2 | fibk |
Financing Receivable Modifications Recorded Investment Accrual Method
FinancingReceivableModificationsRecordedInvestmentAccrualMethod
|
20500000 | usd |
CY2022Q2 | us-gaap |
Long Term Accounts Notes And Loans Receivable Net Noncurrent
LongTermAccountsNotesAndLoansReceivableNetNoncurrent
|
200000 | usd |
CY2021Q4 | us-gaap |
Loans And Leases Receivable Impaired Commitment To Lend
LoansAndLeasesReceivableImpairedCommitmentToLend
|
0 | usd |
CY2021Q4 | us-gaap |
Financing Receivable Modifications Recorded Investment
FinancingReceivableModificationsRecordedInvestment
|
6200000 | usd |
CY2021Q4 | fibk |
Financing Receivable Modifications Recorded Investment Non Accrual
FinancingReceivableModificationsRecordedInvestmentNonAccrual
|
3900000 | usd |
CY2021Q4 | fibk |
Financing Receivable Modifications Recorded Investment Accrual Method
FinancingReceivableModificationsRecordedInvestmentAccrualMethod
|
2300000 | usd |
CY2022Q2 | us-gaap |
Financing Receivable Modifications Post Modification Recorded Investment2
FinancingReceivableModificationsPostModificationRecordedInvestment2
|
6400000 | usd |
us-gaap |
Financing Receivable Modifications Post Modification Recorded Investment2
FinancingReceivableModificationsPostModificationRecordedInvestment2
|
23600000 | usd | |
CY2022Q2 | us-gaap |
Financing Receivable Modifications Number Of Contracts2
FinancingReceivableModificationsNumberOfContracts2
|
4 | note |
CY2022Q2 | us-gaap |
Financing Receivable Modifications Post Modification Recorded Investment2
FinancingReceivableModificationsPostModificationRecordedInvestment2
|
6400000 | usd |
us-gaap |
Financing Receivable Modifications Number Of Contracts2
FinancingReceivableModificationsNumberOfContracts2
|
9 | note | |
us-gaap |
Financing Receivable Modifications Post Modification Recorded Investment2
FinancingReceivableModificationsPostModificationRecordedInvestment2
|
23600000 | usd | |
us-gaap |
Financing Receivables Impaired Troubled Debt Restructuring Write Down
FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown
|
0 | usd | |
us-gaap |
Financing Receivables Impaired Troubled Debt Restructuring Write Down
FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown
|
0 | usd | |
CY2021Q2 | us-gaap |
Financing Receivables Impaired Troubled Debt Restructuring Write Down
FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown
|
0 | usd |
CY2022Q2 | us-gaap |
Financing Receivables Impaired Troubled Debt Restructuring Write Down
FinancingReceivablesImpairedTroubledDebtRestructuringWriteDown
|
0 | usd |
us-gaap |
Financing Receivable Modifications Subsequent Default Recorded Investment1
FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
|
0 | usd | |
CY2022Q2 | us-gaap |
Financing Receivable Modifications Subsequent Default Recorded Investment1
FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
|
0 | usd |
CY2022Q2 | us-gaap |
Impaired Financing Receivable Recorded Investment
ImpairedFinancingReceivableRecordedInvestment
|
190800000 | usd |
CY2022Q1 | us-gaap |
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Acquired During Period Cash Flows Expected To Be Collected At Acquisition
CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAcquiredDuringPeriodCashFlowsExpectedToBeCollectedAtAcquisition
|
623300000 | usd |
CY2022Q1 | us-gaap |
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Allowance For Loan Losses
CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAllowanceForLoanLosses
|
298200000 | usd |
CY2022Q1 | fibk |
Certain Loans And Debt Securities Acquired In Transfer Discount At Acquisition
CertainLoansAndDebtSecuritiesAcquiredInTransferDiscountAtAcquisition
|
57700000 | usd |
CY2022Q1 | fibk |
Certain Loans And Debt Securities Acquired In Transfer Par Value At Acquisition
CertainLoansAndDebtSecuritiesAcquiredInTransferParValueAtAcquisition
|
979200000 | usd |
CY2022Q1 | us-gaap |
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Allowance For Loan Losses
CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAllowanceForLoanLosses
|
298200000 | usd |
CY2022Q1 | us-gaap |
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Allowance For Loan Losses Decreases1
CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesAllowanceForLoanLossesDecreases1
|
238700000 | usd |
CY2022Q1 | fibk |
Business Combination Impact On Purchased Credit Deteriorated Loans
BusinessCombinationImpactOnPurchasedCreditDeterioratedLoans
|
59500000 | usd |
CY2022Q1 | fibk |
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Difference Between Amortized Cost Basis And Unpaid Principal Balance
CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesDifferenceBetweenAmortizedCostBasisAndUnpaidPrincipalBalance
|
39600000 | usd |
CY2022Q1 | fibk |
Certain Loans Acquired In Transfer Not Accounted For As Debt Securities Interest Applied To Principal
CertainLoansAcquiredInTransferNotAccountedForAsDebtSecuritiesInterestAppliedToPrincipal
|
18100000 | usd |
CY2021Q2 | us-gaap |
Loans And Leases Receivable Commitments To Purchase Or Sell
LoansAndLeasesReceivableCommitmentsToPurchaseOrSell
|
0 | usd |
us-gaap |
Loans And Leases Receivable Commitments To Purchase Or Sell
LoansAndLeasesReceivableCommitmentsToPurchaseOrSell
|
0 | usd | |
us-gaap |
Loans And Leases Receivable Commitments To Purchase Or Sell
LoansAndLeasesReceivableCommitmentsToPurchaseOrSell
|
0 | usd | |
CY2022Q2 | us-gaap |
Loans And Leases Receivable Commitments To Purchase Or Sell
LoansAndLeasesReceivableCommitmentsToPurchaseOrSell
|
0 | usd |
CY2022Q2 | us-gaap |
Proceeds From Sale Of Loans Held For Investment
ProceedsFromSaleOfLoansHeldForInvestment
|
0 | usd |
CY2022Q2 | us-gaap |
Proceeds From Sale Of Loans Held For Investment
ProceedsFromSaleOfLoansHeldForInvestment
|
0 | usd |
CY2022Q2 | us-gaap |
Proceeds From Sale Of Loans Held For Investment
ProceedsFromSaleOfLoansHeldForInvestment
|
0 | usd |
CY2021Q2 | us-gaap |
Proceeds From Sale Of Loans Held For Investment
ProceedsFromSaleOfLoansHeldForInvestment
|
0 | usd |
CY2022Q1 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
17500000 | usd |
CY2021Q1 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
2200000 | usd |
CY2021Q4 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
2000000.0 | usd |
CY2020Q4 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
2500000 | usd |
CY2022Q2 | fibk |
Real Estate Acquired Through Foreclosure Acquired Through Acquisition
RealEstateAcquiredThroughForeclosureAcquiredThroughAcquisition
|
0 | usd |
CY2021Q2 | fibk |
Real Estate Acquired Through Foreclosure Acquired Through Acquisition
RealEstateAcquiredThroughForeclosureAcquiredThroughAcquisition
|
0 | usd |
fibk |
Real Estate Acquired Through Foreclosure Acquired Through Acquisition
RealEstateAcquiredThroughForeclosureAcquiredThroughAcquisition
|
15800000 | usd | |
fibk |
Real Estate Acquired Through Foreclosure Acquired Through Acquisition
RealEstateAcquiredThroughForeclosureAcquiredThroughAcquisition
|
0 | usd | |
CY2022Q2 | fibk |
Real Estate Acquired Through Foreclosure Additions
RealEstateAcquiredThroughForeclosureAdditions
|
100000 | usd |
CY2021Q2 | fibk |
Real Estate Acquired Through Foreclosure Additions
RealEstateAcquiredThroughForeclosureAdditions
|
0 | usd |
fibk |
Real Estate Acquired Through Foreclosure Additions
RealEstateAcquiredThroughForeclosureAdditions
|
100000 | usd | |
fibk |
Real Estate Acquired Through Foreclosure Additions
RealEstateAcquiredThroughForeclosureAdditions
|
300000 | usd | |
CY2022Q2 | fibk |
Real Estate Acquired Through Foreclosure Disposals
RealEstateAcquiredThroughForeclosureDisposals
|
800000 | usd |
CY2021Q2 | fibk |
Real Estate Acquired Through Foreclosure Disposals
RealEstateAcquiredThroughForeclosureDisposals
|
200000 | usd |
fibk |
Real Estate Acquired Through Foreclosure Disposals
RealEstateAcquiredThroughForeclosureDisposals
|
1100000 | usd | |
fibk |
Real Estate Acquired Through Foreclosure Disposals
RealEstateAcquiredThroughForeclosureDisposals
|
800000 | usd | |
CY2022Q2 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
16800000 | usd |
CY2021Q2 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
2000000.0 | usd |
CY2022Q2 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
16800000 | usd |
CY2021Q2 | us-gaap |
Real Estate Acquired Through Foreclosure
RealEstateAcquiredThroughForeclosure
|
2000000.0 | usd |
CY2022Q2 | fibk |
Foreclosed Residential Real Estateincludedin Other Real Estate Owned
ForeclosedResidentialRealEstateincludedinOtherRealEstateOwned
|
0 | usd |
CY2022Q2 | us-gaap |
Mortgage Loans In Process Of Foreclosure Amount
MortgageLoansInProcessOfForeclosureAmount
|
0 | usd |
CY2022Q2 | us-gaap |
Interest Rate Cash Flow Hedge Gain Loss To Be Reclassified During Next12 Months Net
InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Liability
DerivativeFairValueOfDerivativeLiability
|
18200000 | usd |
CY2022Q2 | fibk |
Fee Incomeon Derivatives
FeeIncomeonDerivatives
|
usd | |
CY2022Q2 | us-gaap |
Derivative Instruments And Hedges
DerivativeInstrumentsAndHedges
|
189500000 | usd |
CY2022Q2 | us-gaap |
Hedged Asset Fair Value Hedge Cumulative Increase Decrease
HedgedAssetFairValueHedgeCumulativeIncreaseDecrease
|
-10500000 | usd |
CY2021Q4 | us-gaap |
Derivative Instruments And Hedges
DerivativeInstrumentsAndHedges
|
695600000 | usd |
CY2021Q4 | us-gaap |
Hedged Asset Fair Value Hedge Cumulative Increase Decrease
HedgedAssetFairValueHedgeCumulativeIncreaseDecrease
|
-4400000 | usd |
CY2022Q2 | us-gaap |
Derivative Asset Notional Amount
DerivativeAssetNotionalAmount
|
2021900000 | usd |
CY2022Q2 | us-gaap |
Interest Rate Derivative Assets At Fair Value
InterestRateDerivativeAssetsAtFairValue
|
24800000 | usd |
CY2021Q4 | us-gaap |
Derivative Asset Notional Amount
DerivativeAssetNotionalAmount
|
1691200000 | usd |
CY2021Q4 | us-gaap |
Interest Rate Derivative Assets At Fair Value
InterestRateDerivativeAssetsAtFairValue
|
28100000 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Notional Amount
DerivativeLiabilityNotionalAmount
|
1867200000 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Liability
DerivativeFairValueOfDerivativeLiability
|
99400000 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Notional Amount
DerivativeLiabilityNotionalAmount
|
1103900000 | usd |
CY2021Q4 | us-gaap |
Interest Rate Derivative Liabilities At Fair Value
InterestRateDerivativeLiabilitiesAtFairValue
|
18200000 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Asset
DerivativeFairValueOfDerivativeAsset
|
24800000 | usd |
CY2022Q2 | us-gaap |
Derivative Asset Fair Value Gross Liability
DerivativeAssetFairValueGrossLiability
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Assets
DerivativeAssets
|
24800000 | usd |
CY2022Q2 | us-gaap |
Derivative Collateral Obligation To Return Securities
DerivativeCollateralObligationToReturnSecurities
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Collateral Obligation To Return Cash
DerivativeCollateralObligationToReturnCash
|
23700000 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral
DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral
|
1100000 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Asset
DerivativeFairValueOfDerivativeAsset
|
24800000 | usd |
CY2022Q2 | us-gaap |
Derivative Asset Fair Value Gross Liability
DerivativeAssetFairValueGrossLiability
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Assets Liabilities At Fair Value Net
DerivativeAssetsLiabilitiesAtFairValueNet
|
24800000 | usd |
CY2022Q2 | us-gaap |
Derivative Collateral Obligation To Return Securities
DerivativeCollateralObligationToReturnSecurities
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Collateral Obligation To Return Cash
DerivativeCollateralObligationToReturnCash
|
23700000 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral
DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral
|
1100000 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Liability
DerivativeFairValueOfDerivativeLiability
|
99400000 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Fair Value Gross Asset
DerivativeLiabilityFairValueGrossAsset
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Liabilities
DerivativeLiabilities
|
99400000 | usd |
CY2022Q2 | us-gaap |
Derivative Collateral Right To Reclaim Securities
DerivativeCollateralRightToReclaimSecurities
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Collateral Right To Reclaim Cash
DerivativeCollateralRightToReclaimCash
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral
DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral
|
99400000 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Gross
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedGross
|
1334100000 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Fair Value Gross Asset
DerivativeLiabilityFairValueGrossAsset
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoaned
|
1334100000 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Securities
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimSecurities
|
0 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Cash
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimCash
|
1234700000 | usd |
CY2022Q2 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Amount Offset Against Collateral
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAmountOffsetAgainstCollateral
|
99400000 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Asset
DerivativeFairValueOfDerivativeAsset
|
28100000 | usd |
CY2021Q4 | us-gaap |
Derivative Asset Fair Value Gross Liability
DerivativeAssetFairValueGrossLiability
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Assets
DerivativeAssets
|
28100000 | usd |
CY2021Q4 | us-gaap |
Derivative Collateral Obligation To Return Securities
DerivativeCollateralObligationToReturnSecurities
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Collateral Obligation To Return Cash
DerivativeCollateralObligationToReturnCash
|
8000000.0 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral
DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral
|
20100000 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Asset
DerivativeFairValueOfDerivativeAsset
|
28100000 | usd |
CY2021Q4 | us-gaap |
Derivative Asset Fair Value Gross Liability
DerivativeAssetFairValueGrossLiability
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Assets
DerivativeAssets
|
28100000 | usd |
CY2021Q4 | us-gaap |
Derivative Collateral Obligation To Return Securities
DerivativeCollateralObligationToReturnSecurities
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Collateral Obligation To Return Cash
DerivativeCollateralObligationToReturnCash
|
8000000.0 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral
DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral
|
20100000 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Liability
DerivativeFairValueOfDerivativeLiability
|
18200000 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Fair Value Gross Asset
DerivativeLiabilityFairValueGrossAsset
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Liabilities
DerivativeLiabilities
|
18200000 | usd |
CY2021Q4 | us-gaap |
Derivative Collateral Right To Reclaim Securities
DerivativeCollateralRightToReclaimSecurities
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Collateral Right To Reclaim Cash
DerivativeCollateralRightToReclaimCash
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral
DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral
|
18200000 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase Gross
SecuritiesSoldUnderAgreementsToRepurchaseGross
|
1051100000 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase Asset
SecuritiesSoldUnderAgreementsToRepurchaseAsset
|
0 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase
SecuritiesSoldUnderAgreementsToRepurchase
|
1051100000 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase Collateral Right To Reclaim Securities
SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimSecurities
|
0 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase Collateral Right To Reclaim Cash
SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimCash
|
1051100000 | usd |
CY2021Q4 | us-gaap |
Securities Sold Under Agreements To Repurchase Amount Offset Against Collateral
SecuritiesSoldUnderAgreementsToRepurchaseAmountOffsetAgainstCollateral
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Gross
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedGross
|
1069300000 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Asset
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAsset
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoaned
|
1069300000 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Securities
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimSecurities
|
0 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Cash
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimCash
|
1051100000 | usd |
CY2021Q4 | us-gaap |
Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Amount Offset Against Collateral
DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAmountOffsetAgainstCollateral
|
18200000 | usd |
us-gaap |
Accelerated Share Repurchases Adjustment To Recorded Amount
AcceleratedShareRepurchasesAdjustmentToRecordedAmount
|
64300000 | usd | |
us-gaap |
Treasury Stock Acquired Average Cost Per Share
TreasuryStockAcquiredAverageCostPerShare
|
37.38 | ||
fibk |
Shares Repurchased During The Period As Percentage Of Shares Authorized For Repurchase Percent
SharesRepurchasedDuringThePeriodAsPercentageOfSharesAuthorizedForRepurchasePercent
|
0.344 | ||
CY2020Q3 | us-gaap |
Stock Repurchase Program Number Of Shares Authorized To Be Repurchased
StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased
|
5000000 | shares |
CY2022Q2 | us-gaap |
Common Stock Shares Issued
CommonStockSharesIssued
|
107758038 | shares |
CY2022Q2 | us-gaap |
Common Stock Shares Outstanding
CommonStockSharesOutstanding
|
107758038 | shares |
CY2022Q2 | us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
109131718 | shares |
CY2021Q2 | us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
61727821 | shares |
us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
101076331 | shares | |
CY2022Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
64100000 | usd |
CY2021Q2 | us-gaap |
Net Income Loss
NetIncomeLoss
|
42500000 | usd |
us-gaap |
Net Income Loss
NetIncomeLoss
|
30700000 | usd | |
us-gaap |
Net Income Loss
NetIncomeLoss
|
93900000 | usd | |
CY2022Q2 | us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
109106891 | shares |
CY2021Q2 | us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
61657593 | shares |
us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
101025926 | shares | |
us-gaap |
Weighted Average Number Of Shares Outstanding Basic
WeightedAverageNumberOfSharesOutstandingBasic
|
61624917 | shares | |
CY2022Q2 | us-gaap |
Incremental Common Shares Attributable To Share Based Payment Arrangements
IncrementalCommonSharesAttributableToShareBasedPaymentArrangements
|
24827 | shares |
CY2021Q2 | us-gaap |
Incremental Common Shares Attributable To Share Based Payment Arrangements
IncrementalCommonSharesAttributableToShareBasedPaymentArrangements
|
70228 | shares |
us-gaap |
Incremental Common Shares Attributable To Share Based Payment Arrangements
IncrementalCommonSharesAttributableToShareBasedPaymentArrangements
|
50405 | shares | |
us-gaap |
Incremental Common Shares Attributable To Share Based Payment Arrangements
IncrementalCommonSharesAttributableToShareBasedPaymentArrangements
|
98225 | shares | |
us-gaap |
Weighted Average Number Of Diluted Shares Outstanding
WeightedAverageNumberOfDilutedSharesOutstanding
|
61723142 | shares | |
CY2022Q2 | us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
0.59 | |
CY2021Q2 | us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
0.69 | |
us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
0.30 | ||
us-gaap |
Earnings Per Share Basic
EarningsPerShareBasic
|
1.52 | ||
CY2022Q2 | us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
0.59 | |
CY2021Q2 | us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
0.69 | |
us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
0.30 | ||
us-gaap |
Earnings Per Share Diluted
EarningsPerShareDiluted
|
1.52 | ||
CY2022Q2 | us-gaap |
Capital
Capital
|
2908700000 | usd |
CY2022Q2 | us-gaap |
Capital To Risk Weighted Assets
CapitalToRiskWeightedAssets
|
0.1360 | |
CY2022Q2 | us-gaap |
Capital Required For Capital Adequacy
CapitalRequiredForCapitalAdequacy
|
1710700000 | usd |
CY2022Q2 | us-gaap |
Capital Required For Capital Adequacy To Risk Weighted Assets
CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
|
0.0800 | |
CY2022Q2 | fibk |
Capital Required For Capital Adequacy Under Basel Iii Fully Phased In
CapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedIn
|
2245200000 | usd |
CY2022Q2 | fibk |
Capital Required For Capital Adequacy Under Basel Iii Fully Phased In To Risk Weighted Assets
CapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedInToRiskWeightedAssets
|
0.1050 | |
CY2022Q2 | us-gaap |
Capital Required To Be Well Capitalized
CapitalRequiredToBeWellCapitalized
|
2138300000 | usd |
CY2022Q2 | us-gaap |
Capital Required To Be Well Capitalized To Risk Weighted Assets
CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
|
0.1000 | |
CY2022Q2 | us-gaap |
Tier One Risk Based Capital
TierOneRiskBasedCapital
|
2451400000 | usd |
CY2022Q2 | us-gaap |
Tier One Risk Based Capital To Risk Weighted Assets
TierOneRiskBasedCapitalToRiskWeightedAssets
|
0.1146 | |
CY2022Q2 | us-gaap |
Tier One Risk Based Capital Required For Capital Adequacy
TierOneRiskBasedCapitalRequiredForCapitalAdequacy
|
1283000000 | usd |
CY2022Q2 | us-gaap |
Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets
TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
|
0.0600 | |
CY2022Q2 | fibk |
Tier One Capital Required For Capital Adequacy Under Basel Iii Fully Phased In
TierOneCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedIn
|
1817600000 | usd |
CY2022Q2 | fibk |
Tier One Capital Required For Capital Adequacy Under Basel Iii Fully Phased In To Risk Weighted Assets
TierOneCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedInToRiskWeightedAssets
|
0.0850 | |
CY2022Q2 | us-gaap |
Tier One Risk Based Capital Required To Be Well Capitalized
TierOneRiskBasedCapitalRequiredToBeWellCapitalized
|
1710700000 | usd |
CY2022Q2 | us-gaap |
Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets
TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
|
0.0800 | |
CY2022Q2 | us-gaap |
Common Equity Tier One Capital
CommonEquityTierOneCapital
|
2451400000 | usd |
CY2022Q2 | us-gaap |
Common Equity Tier One Capital Ratio
CommonEquityTierOneCapitalRatio
|
0.1146 | |
CY2022Q2 | us-gaap |
Common Equity Tier One Capital Required For Capital Adequacy
CommonEquityTierOneCapitalRequiredForCapitalAdequacy
|
962200000 | usd |
CY2022Q2 | us-gaap |
Banking Regulation Common Equity Tier One Risk Based Capital Ratio Capital Adequacy Minimum
BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum
|
0.0450 | |
CY2022Q2 | fibk |
Tier One Common Equity Capital Required For Capital Adequacy Under Basel Iii Fully Phased In
TierOneCommonEquityCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedIn
|
1496800000 | usd |
CY2022Q2 | fibk |
Tier One Common Equity Capital Required For Capital Adequacy Under Basel Iii Fully Phased In To Risk Weighted Assets
TierOneCommonEquityCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedInToRiskWeightedAssets
|
0.0700 | |
CY2022Q2 | us-gaap |
Common Equity Tier One Capital Required To Be Well Capitalized
CommonEquityTierOneCapitalRequiredToBeWellCapitalized
|
1389900000 | usd |
CY2022Q2 | us-gaap |
Banking Regulation Common Equity Tier One Risk Based Capital Ratio Well Capitalized Minimum
BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum
|
0.0650 | |
CY2022Q2 | us-gaap |
Tier One Leverage Capital
TierOneLeverageCapital
|
2451400000 | usd |
CY2022Q2 | us-gaap |
Tier One Leverage Capital To Average Assets
TierOneLeverageCapitalToAverageAssets
|
0.0772 | |
CY2022Q2 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy
TierOneLeverageCapitalRequiredForCapitalAdequacy
|
1269500000 | usd |
CY2022Q2 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy To Average Assets
TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
|
0.0400 | |
CY2022Q2 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy
TierOneLeverageCapitalRequiredForCapitalAdequacy
|
1269500000 | usd |
CY2022Q2 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy To Average Assets
TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
|
0.0400 | |
CY2022Q2 | us-gaap |
Tier One Leverage Capital Required To Be Well Capitalized
TierOneLeverageCapitalRequiredToBeWellCapitalized
|
1586800000 | usd |
CY2022Q2 | us-gaap |
Tier One Leverage Capital Required To Be Well Capitalized To Average Assets
TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
|
0.0500 | |
CY2021Q4 | us-gaap |
Capital
Capital
|
1659300000 | usd |
CY2021Q4 | us-gaap |
Capital To Risk Weighted Assets
CapitalToRiskWeightedAssets
|
0.1411 | |
CY2021Q4 | us-gaap |
Capital Required For Capital Adequacy
CapitalRequiredForCapitalAdequacy
|
940900000 | usd |
CY2021Q4 | us-gaap |
Capital Required For Capital Adequacy To Risk Weighted Assets
CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
|
0.0800 | |
CY2021Q4 | fibk |
Capital Required For Capital Adequacy Under Basel Iii Fully Phased In
CapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedIn
|
1235000000 | usd |
CY2021Q4 | fibk |
Capital Required For Capital Adequacy Under Basel Iii Fully Phased In To Risk Weighted Assets
CapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedInToRiskWeightedAssets
|
0.1050 | |
CY2021Q4 | us-gaap |
Capital Required To Be Well Capitalized
CapitalRequiredToBeWellCapitalized
|
1176200000 | usd |
CY2021Q4 | us-gaap |
Capital Required To Be Well Capitalized To Risk Weighted Assets
CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
|
0.1000 | |
CY2021Q4 | us-gaap |
Tier One Risk Based Capital
TierOneRiskBasedCapital
|
1469000000 | usd |
CY2021Q4 | us-gaap |
Tier One Risk Based Capital To Risk Weighted Assets
TierOneRiskBasedCapitalToRiskWeightedAssets
|
0.1249 | |
CY2021Q4 | us-gaap |
Tier One Risk Based Capital Required For Capital Adequacy
TierOneRiskBasedCapitalRequiredForCapitalAdequacy
|
705700000 | usd |
CY2021Q4 | us-gaap |
Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets
TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
|
0.0600 | |
CY2021Q4 | fibk |
Tier One Capital Required For Capital Adequacy Under Basel Iii Fully Phased In
TierOneCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedIn
|
999700000 | usd |
CY2021Q4 | fibk |
Tier One Capital Required For Capital Adequacy Under Basel Iii Fully Phased In To Risk Weighted Assets
TierOneCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedInToRiskWeightedAssets
|
0.0850 | |
CY2021Q4 | us-gaap |
Tier One Risk Based Capital Required To Be Well Capitalized
TierOneRiskBasedCapitalRequiredToBeWellCapitalized
|
940900000 | usd |
CY2021Q4 | us-gaap |
Tier One Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets
TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
|
0.0800 | |
CY2021Q4 | us-gaap |
Common Equity Tier One Capital
CommonEquityTierOneCapital
|
1384800000 | usd |
CY2021Q4 | us-gaap |
Common Equity Tier One Capital Ratio
CommonEquityTierOneCapitalRatio
|
0.1177 | |
CY2021Q4 | us-gaap |
Common Equity Tier One Capital Required For Capital Adequacy
CommonEquityTierOneCapitalRequiredForCapitalAdequacy
|
529300000 | usd |
CY2021Q4 | us-gaap |
Banking Regulation Common Equity Tier One Risk Based Capital Ratio Capital Adequacy Minimum
BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioCapitalAdequacyMinimum
|
0.0450 | |
CY2021Q4 | fibk |
Tier One Common Equity Capital Required For Capital Adequacy Under Basel Iii Fully Phased In
TierOneCommonEquityCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedIn
|
823300000 | usd |
CY2021Q4 | fibk |
Tier One Common Equity Capital Required For Capital Adequacy Under Basel Iii Fully Phased In To Risk Weighted Assets
TierOneCommonEquityCapitalRequiredForCapitalAdequacyUnderBaselIIIFullyPhasedInToRiskWeightedAssets
|
0.0700 | |
CY2021Q4 | us-gaap |
Common Equity Tier One Capital Required To Be Well Capitalized
CommonEquityTierOneCapitalRequiredToBeWellCapitalized
|
764500000 | usd |
CY2021Q4 | us-gaap |
Banking Regulation Common Equity Tier One Risk Based Capital Ratio Well Capitalized Minimum
BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum
|
0.0650 | |
CY2021Q4 | us-gaap |
Tier One Leverage Capital
TierOneLeverageCapital
|
1469000000 | usd |
CY2021Q4 | us-gaap |
Tier One Leverage Capital To Average Assets
TierOneLeverageCapitalToAverageAssets
|
0.0768 | |
CY2021Q4 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy
TierOneLeverageCapitalRequiredForCapitalAdequacy
|
765500000 | usd |
CY2021Q4 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy To Average Assets
TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
|
0.0400 | |
CY2021Q4 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy
TierOneLeverageCapitalRequiredForCapitalAdequacy
|
765500000 | usd |
CY2021Q4 | us-gaap |
Tier One Leverage Capital Required For Capital Adequacy To Average Assets
TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
|
0.0400 | |
CY2021Q4 | us-gaap |
Tier One Leverage Capital Required To Be Well Capitalized
TierOneLeverageCapitalRequiredToBeWellCapitalized
|
956900000 | usd |
CY2021Q4 | us-gaap |
Tier One Leverage Capital Required To Be Well Capitalized To Average Assets
TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
|
0.0500 | |
CY2020Q1 | us-gaap |
Income Tax Effects Allocated Directly To Equity Cumulative Effect Of Change In Accounting Principle
IncomeTaxEffectsAllocatedDirectlyToEquityCumulativeEffectOfChangeInAccountingPrinciple
|
24100000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-161600000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-800000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax
|
-45200000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax
|
-200000 | usd |
CY2022Q1 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
6200000 | usd |
CY2021Q1 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
3400000 | usd |
CY2021Q4 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
3800000 | usd |
CY2020Q4 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
3700000 | usd |
CY2022Q2 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
6200000 | usd |
CY2021Q2 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
3400000 | usd |
CY2022Q2 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
6200000 | usd |
CY2021Q2 | us-gaap |
Off Balance Sheet Credit Loss Liability
OffBalanceSheetCreditLossLiability
|
3400000 | usd |
CY2022Q2 | fibk |
Credit Extension Commitments
CreditExtensionCommitments
|
4840800000 | usd |
CY2021Q4 | fibk |
Credit Extension Commitments
CreditExtensionCommitments
|
2539800000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
|
-116400000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
|
-600000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-100000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-100000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax
|
0 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax
|
0 | usd |
CY2022Q2 | us-gaap |
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax
ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
|
-100000 | usd |
CY2021Q2 | us-gaap |
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax
ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
|
-100000 | usd |
CY2022Q2 | us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Before Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossBeforeTax
|
900000 | usd |
CY2021Q2 | us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Before Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossBeforeTax
|
-24800000 | usd |
CY2022Q2 | us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossTax
|
200000 | usd |
CY2021Q2 | us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossTax
|
-6300000 | usd |
CY2022Q2 | us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss After Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossAfterTax
|
700000 | usd |
CY2021Q2 | us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss After Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossAfterTax
|
-18500000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments And Tax
OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsAndTax
|
-15000000.0 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments And Tax
OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsAndTax
|
-800000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax
OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax
|
4200000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax
OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax
|
200000 | usd |
CY2022Q2 | us-gaap |
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net
DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
|
-10800000 | usd |
CY2021Q2 | us-gaap |
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net
DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
|
-600000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
-177400000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
23300000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
-49600000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
5900000 | usd |
CY2022Q2 | us-gaap |
Other Comprehensive Income Loss Net Of Tax
OtherComprehensiveIncomeLossNetOfTax
|
-127800000 | usd |
CY2021Q2 | us-gaap |
Other Comprehensive Income Loss Net Of Tax
OtherComprehensiveIncomeLossNetOfTax
|
17400000 | usd |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-414200000 | usd | |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax
|
-67600000 | usd | |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax
|
-107900000 | usd | |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax
|
-17200000 | usd | |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
|
-306300000 | usd | |
us-gaap |
Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax
OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax
|
-50400000 | usd | |
us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-200000 | usd | |
us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax
|
-100000 | usd | |
us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax
|
0 | usd | |
us-gaap |
Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax
OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax
|
0 | usd | |
us-gaap |
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax
ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
|
-200000 | usd | |
us-gaap |
Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax
ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
|
-100000 | usd | |
us-gaap |
Other Than Temporary Impairment Losses Investments Reclassification Adjustment Of Noncredit Portion From Heldtomaturity To Availableforsale Securities Before Tax
OtherThanTemporaryImpairmentLossesInvestmentsReclassificationAdjustmentOfNoncreditPortionFromHeldtomaturityToAvailableforsaleSecuritiesBeforeTax
|
-200000 | usd | |
us-gaap |
Other Than Temporary Impairment Losses Investments Reclassification Adjustment Of Noncredit Portion From Heldtomaturity To Availableforsale Securities Before Tax
OtherThanTemporaryImpairmentLossesInvestmentsReclassificationAdjustmentOfNoncreditPortionFromHeldtomaturityToAvailableforsaleSecuritiesBeforeTax
|
0 | usd | |
us-gaap |
Other Comprehensive Loss Held To Maturity Security Reclassification Adjustment From Aoci For Noncredit Portion Of Otti Sale Tax
OtherComprehensiveLossHeldToMaturitySecurityReclassificationAdjustmentFromAociForNoncreditPortionOfOttiSaleTax
|
100000 | usd | |
us-gaap |
Other Comprehensive Loss Held To Maturity Security Reclassification Adjustment From Aoci For Noncredit Portion Of Otti Sale Tax
OtherComprehensiveLossHeldToMaturitySecurityReclassificationAdjustmentFromAociForNoncreditPortionOfOttiSaleTax
|
0 | usd | |
us-gaap |
Other Comprehensive Loss Held To Maturity Security Reclassification Adjustment From Aoci For Noncredit Portion Of Otti Sale After Tax
OtherComprehensiveLossHeldToMaturitySecurityReclassificationAdjustmentFromAociForNoncreditPortionOfOttiSaleAfterTax
|
100000 | usd | |
us-gaap |
Other Comprehensive Loss Held To Maturity Security Reclassification Adjustment From Aoci For Noncredit Portion Of Otti Sale After Tax
OtherComprehensiveLossHeldToMaturitySecurityReclassificationAdjustmentFromAociForNoncreditPortionOfOttiSaleAfterTax
|
0 | usd | |
us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Before Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossBeforeTax
|
23900000 | usd | |
us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Before Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossBeforeTax
|
-24800000 | usd | |
us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossTax
|
5900000 | usd | |
us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossTax
|
-6300000 | usd | |
us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss After Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossAfterTax
|
18000000.0 | usd | |
us-gaap |
Oci Debt Securities Available For Sale Transfer To Held To Maturity Adjustment From Aoci For Amortization Of Gain Loss After Tax
OciDebtSecuritiesAvailableForSaleTransferToHeldToMaturityAdjustmentFromAociForAmortizationOfGainLossAfterTax
|
-18500000 | usd | |
us-gaap |
Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments And Tax
OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsAndTax
|
6300000 | usd | |
us-gaap |
Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Reclassification Adjustments And Tax
OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeReclassificationAdjustmentsAndTax
|
-900000 | usd | |
us-gaap |
Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax
OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax
|
-1100000 | usd | |
us-gaap |
Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax
OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax
|
200000 | usd | |
us-gaap |
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net
DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
|
5200000 | usd | |
us-gaap |
Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net
DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
|
-700000 | usd | |
us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
-431400000 | usd | |
us-gaap |
Other Comprehensive Income Loss Before Tax
OtherComprehensiveIncomeLossBeforeTax
|
-43600000 | usd | |
us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
-112600000 | usd | |
us-gaap |
Other Comprehensive Income Loss Tax
OtherComprehensiveIncomeLossTax
|
-11100000 | usd | |
us-gaap |
Other Comprehensive Income Loss Net Of Tax
OtherComprehensiveIncomeLossNetOfTax
|
-318800000 | usd | |
us-gaap |
Other Comprehensive Income Loss Net Of Tax
OtherComprehensiveIncomeLossNetOfTax
|
-32500000 | usd | |
CY2021 | us-gaap |
Other Comprehensive Income Loss Transfers From Held To Maturity To Available For Sale Securities Net Of Tax
OtherComprehensiveIncomeLossTransfersFromHeldToMaturityToAvailableForSaleSecuritiesNetOfTax
|
15000000.0 | usd |
CY2022Q2 | us-gaap |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Net
FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet
|
0 | usd |
us-gaap |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Net
FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet
|
0 | usd | |
us-gaap |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Net
FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet
|
0 | usd | |
CY2021Q2 | us-gaap |
Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Net
FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet
|
0 | usd |
fibk |
Real Estate Acquired Through Foreclosure Valuation Adjustments
RealEstateAcquiredThroughForeclosureValuationAdjustments
|
0 | usd |