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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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Fair value, after the effects of master netting arrangements, of a financial asset or other 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 assets not subject to a master netting arrangement and not elected to be offset.

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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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No definition available.

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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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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.

+ References

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.

+ References

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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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 ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Derivative Financial Instruments
Notional Amount	$ 20,394,696		$ 20,394,696		$ 19,342,657
Estimated Fair Value Gain			526,145		813,899
Estimated Fair Value Loss			518,221		804,832
Interest Rate Derivative Assets, at Fair Value	516,600		516,600		802,800
Interest Rate Derivative Liabilities, at Fair Value	516,600		516,600		802,700
Interest Rate Derivatives, at Fair Value, Net	6		6		17
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	(518,221)		(518,221)		(804,832)
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	402,636		402,636		510,730
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	348,530		348,530		411,273
Cash flow hedge \| Borrower
Derivative Financial Instruments
Collateral provided	414,500		414,500
Interest rate contracts
Derivative Financial Instruments
Notional Amount	19,800,000		19,800,000		18,600,000
Mortgage servicing rights hedging \| Non-designated hedges
Derivative Financial Instruments
Notional Amount	170,000		170,000		149,000
Estimated gain (loss) on fair value			586	$ 603
Mortgage servicing rights hedging \| Non-designated hedges \| Other Assets and Other Liabilities
Derivative Financial Instruments
Notional Amount	170,000		170,000		149,000
Estimated Fair Value Gain			586		119
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	9,426		9,426		15,328
Mortgage loan pipeline commitments hedging \| Non-designated hedges \| Other Assets
Derivative Financial Instruments
Notional Amount	386,500		386,500		528,500
Estimated Fair Value Gain			8,927		11,017
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	386,500		386,500		528,500
Fair value of forward commitments	(500)		(500)
Fair value of forward commitments					(4,311)
Customer swaps \| Cash flow hedge \| Investment securities - available for sale
Derivative Financial Instruments
Collateral provided	443,000		443,000
Foreign exchange swaps
Derivative Financial Instruments
Gain or loss recorded	0	$ 0
Interest rate swap \| Fair Value Hedging \| Counterparty
Derivative Financial Instruments
Notional Amount	16,200		16,200		16,400
Gain or loss recorded	0		0
Interest rate swap \| Fair Value Hedging \| Other Liabilities \| Counterparty
Derivative Financial Instruments
Notional Amount	16,175		16,175		16,439
Estimated Fair Value Loss			1,583		2,086
Interest rate swap \| Non-designated hedges \| Other Assets and Other Liabilities \| Borrower
Derivative Financial Instruments
Notional Amount	9,906,849		9,906,849		9,324,359
Estimated Fair Value Gain			516,632		802,717
Estimated Fair Value Loss			46,982		46
Interest rate swap \| Non-designated hedges \| Other Assets and Other Liabilities \| Counterparty
Derivative Financial Instruments
Notional Amount	$ 9,915,172		9,915,172		9,324,359
Estimated Fair Value Gain					46
Estimated Fair Value Loss			$ 469,656		$ 802,700