Derivatives (Derivatives Not Designated as Hedging Instruments - Interest Rate Contracts) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Derivative assets - Fair value	$ 689,100	$ 484,184
Derivative liabilities - Fair value	692,029	390,171
Derivatives not designated as hedging instruments
Derivative [Line Items]
Notional Amount	20,259,808	19,522,661
Derivative assets - Fair value	688,715	484,184
Derivative liabilities - Fair value	691,539	389,889
Derivatives not designated as hedging instruments \| Interest rate contracts
Derivative [Line Items]
Notional Amount	17,771,724	17,575,420
Derivative assets - Fair value	187,716	240,222
Derivative liabilities - Fair value	236,569	179,905
Derivatives not designated as hedging instruments \| Financial Counterparty \| Interest rate contracts
Derivative [Line Items]
Notional Amount	8,900,000	8,800,000
Interest rate contracts \| Derivatives not designated as hedging instruments \| Customer Counterparty \| Written options
Derivative [Line Items]
Notional Amount	1,460,907	1,118,074
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	13,804	2,148
Interest rate contracts \| Derivatives not designated as hedging instruments \| Customer Counterparty \| Sold collars and corridors
Derivative [Line Items]
Notional Amount	210,909	194,181
Derivative assets - Fair value	307	1,272
Derivative liabilities - Fair value	3,869	642
Interest rate contracts \| Derivatives not designated as hedging instruments \| Customer Counterparty \| Swaps
Derivative [Line Items]
Notional Amount	7,199,663	7,460,836
Derivative assets - Fair value	40,246	211,727
Derivative liabilities - Fair value	193,683	39,650
Interest rate contracts \| Derivatives not designated as hedging instruments \| Customer Counterparty \| Interest rate contracts
Derivative [Line Items]
Notional Amount	8,871,479	8,773,091
Derivative assets - Fair value	40,553	212,999
Derivative liabilities - Fair value	211,356	42,440
Interest rate contracts \| Derivatives not designated as hedging instruments \| Financial Counterparty \| Purchased options
Derivative [Line Items]
Notional Amount	1,460,907	1,118,074
Derivative assets - Fair value	13,867	2,159
Derivative liabilities - Fair value	0	0
Interest rate contracts \| Derivatives not designated as hedging instruments \| Financial Counterparty \| Collars and corridors
Derivative [Line Items]
Notional Amount	210,910	194,181
Derivative assets - Fair value	3,896	646
Derivative liabilities - Fair value	307	1,275
Interest rate contracts \| Derivatives not designated as hedging instruments \| Financial Counterparty \| Swaps
Derivative [Line Items]
Notional Amount	7,228,428	7,490,074
Derivative assets - Fair value	129,400	24,418
Derivative liabilities - Fair value	24,906	136,190
Interest rate contracts \| Derivatives not designated as hedging instruments \| Financial Counterparty \| Interest rate contracts
Derivative [Line Items]
Notional Amount	8,900,245	8,802,329
Derivative assets - Fair value	147,163	27,223
Derivative liabilities - Fair value	$ 25,213	$ 137,465

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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- Definition

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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