Derivatives (Derivatives Not Designated as Hedging Instruments - Interest Rate Contracts) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative assets - Fair value	$ 484,184	$ 602,754
Derivative liabilities - Fair Value	390,171	424,828
Derivative instruments not designated as hedging instruments
Derivative [Line Items]
Notional amount	19,522,661	21,341,158
Derivative assets - Fair value	484,184	602,754
Derivative liabilities - Fair Value	389,889	422,729
Derivative instruments not designated as hedging instruments \| Interest rate contracts
Derivative [Line Items]
Notional amount	17,575,420	18,155,678
Derivative assets - Fair value	240,222	489,132
Derivative liabilities - Fair Value	179,905	315,834
Derivative instruments not designated as hedging instruments \| Financial Counterparty \| Interest rate contracts
Derivative [Line Items]
Notional amount	8,800,000	9,090,000
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Customer Counterparty \| Written options
Derivative [Line Items]
Notional amount	1,118,074	957,393
Derivative assets - Fair value	0	0
Derivative liabilities - Fair Value	2,148	115
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Customer Counterparty \| Sold collars and corridors
Derivative [Line Items]
Notional amount	194,181	518,477
Derivative assets - Fair value	1,272	7,673
Derivative liabilities - Fair Value	642	0
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Customer Counterparty \| Swaps
Derivative [Line Items]
Notional amount	7,460,836	7,586,414
Derivative assets - Fair value	211,727	479,634
Derivative liabilities - Fair Value	39,650	1,364
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Customer Counterparty \| Interest rate contracts
Derivative [Line Items]
Notional amount	8,773,091	9,062,284
Derivative assets - Fair value	212,999	487,307
Derivative liabilities - Fair Value	42,440	1,479
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Financial Counterparty \| Purchased options
Derivative [Line Items]
Notional amount	1,118,074	957,393
Derivative assets - Fair value	2,159	101
Derivative liabilities - Fair Value	0	15
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Financial Counterparty \| Collars and corridors
Derivative [Line Items]
Notional amount	194,181	518,477
Derivative assets - Fair value	646	0
Derivative liabilities - Fair Value	1,275	7,717
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Financial Counterparty \| Swaps
Derivative [Line Items]
Notional amount	7,490,074	7,617,524
Derivative assets - Fair value	24,418	1,724
Derivative liabilities - Fair Value	136,190	306,623
Interest rate contracts \| Derivative instruments not designated as hedging instruments \| Financial Counterparty \| Interest rate contracts
Derivative [Line Items]
Notional amount	8,802,329	9,093,394
Derivative assets - Fair value	27,223	1,825
Derivative liabilities - Fair Value	$ 137,465	$ 314,355

Fair value, before 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 elected not to be offset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313

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- Definition

Fair value, before 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 elected not to be offset.

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- Definition

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.

+ References

No definition available.

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Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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