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The amount of cost incurred for termination of derivative contract.

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Termination value as of the balance sheet date of all derivatives not designated as hedging instruments.

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Fair value of all asset derivatives designated as cash flow hedging instruments.

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Fair value of all liability derivatives designated as cash flow hedging instruments.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of increase in the fair value of derivatives recognized in the income statement.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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Nominal or face amount used to calculate payment on derivative.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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No definition available.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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No definition available.

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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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No definition available.

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Fair value of financial and nonfinancial obligations.

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Amount, after tax and before reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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Derivative Financial Instruments (Details) - USD ($)	12 Months Ended
Derivative Financial Instruments (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative Financial Instruments
Notional Amount	$ 21,351,715,000	$ 19,342,657,000
Estimated Fair Value Gain	414,742,000	813,899,000
Estimated Fair Value Loss	410,137,000	804,832,000
Gains (losses) on cash flow hedge in other comprehensive income		10,800,000
Cash flow hedge liability	0
Cash flow hedge assets		30,300,000
Ineffectiveness in the cash flow hedge		0
Gain or loss recorded	0	0
Interest Rate Derivative Assets, at Fair Value	408,800,000	802,800,000
Interest Rate Derivative Liabilities, at Fair Value	408,800,000	802,700,000
Interest Rate Derivatives, at Fair Value, Net	5,000	17,000,000,000
Estimated gain (loss) on fair value	1,200,000	(119,000)
Termination value of obligations under agreement		38,800,000
Interest expense	51,629,000	83,564,000	$ 86,552,000
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Fair value of forward commitments	(410,137,000)	(804,832,000)
Mortgage loan pipeline
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	264,000,000,000	510,730,000,000
Expected closures
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	233,265,000,000	411,273,000,000
Cash flow hedge
Derivative Financial Instruments
Collateral provided	0	0
Cash flow hedge \| Borrower
Derivative Financial Instruments
Collateral provided	347,600,000
Interest rate contracts
Derivative Financial Instruments
Notional Amount	20,800,000,000	18,600,000,000
Mortgage servicing rights hedging \| Non-designated hedges
Derivative Financial Instruments
Notional Amount	205,000,000.0	149,000,000.0
Mortgage servicing rights hedging \| Non-designated hedges \| Other Assets and Other Liabilities
Derivative Financial Instruments
Notional Amount	205,000,000	149,000,000
Estimated Fair Value Gain	1,228,000	119,000
Mortgage loan pipeline commitments hedging
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	4,759,000,000	15,328,000,000
Mortgage loan pipeline commitments hedging \| Non-designated hedges \| Other Assets
Derivative Financial Instruments
Notional Amount	324,000,000	528,500,000
Estimated Fair Value Gain	4,738,000	11,017,000
Forward commitments
Obligation under forward commitments, the fair value of those obligations along with the fair value of derivative instruments associated with forward commitments
Obligation	324,000,000,000	528,500,000,000
Fair value of forward commitments	(21,000,000)	(4,311,000,000)
Customer swaps \| Cash flow hedge \| Investment securities - available for sale
Derivative Financial Instruments
Collateral provided	348,800,000
Interest rate swap
Derivative Financial Instruments
Termination cost		40,800,000
Interest expense		2,000,000.0
Interest rate swap \| Fair Value Hedging \| Counterparty
Derivative Financial Instruments
Notional Amount	15,700,000	16,400,000
Interest rate swap \| Fair Value Hedging \| Other Liabilities \| Counterparty
Derivative Financial Instruments
Notional Amount	15,716,000	16,439,000
Estimated Fair Value Loss	1,355,000	2,086,000
Interest rate swap \| Non-designated hedges \| Other Assets and Other Liabilities \| Borrower
Derivative Financial Instruments
Notional Amount	10,404,605,000	9,324,359,000
Estimated Fair Value Gain	408,776,000	802,717,000
Estimated Fair Value Loss	69,998,000	46,000
Interest rate swap \| Non-designated hedges \| Other Assets and Other Liabilities \| Counterparty
Derivative Financial Instruments
Notional Amount	10,402,394,000	9,324,359,000
Estimated Fair Value Gain		46,000
Estimated Fair Value Loss	338,784,000	802,700,000
Foreign exchange contract
Derivative Financial Instruments
Gain or loss recorded	$ 0	$ 0