Derivatives - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Jul. 31, 2017
Derivatives, Fair Value [Line Items]
Notional Amount			$ 100,000
Not designated as hedging
Derivatives, Fair Value [Line Items]
Notional Amount	$ 3,733,274	$ 3,532,227
Asset	65,203	68,938
Liability	29,271	46,333
Not designated as hedging \| Interest rate contracts
Derivatives, Fair Value [Line Items]
Notional Amount	685,330	606,878
Asset	26,419	34,547
Liability	26,272	34,317
Not designated as hedging \| Forward commitments
Derivatives, Fair Value [Line Items]
Notional Amount	1,575,965	1,358,328
Asset	25,835	0
Liability	0	11,633
Not designated as hedging \| Interest rate-lock commitments
Derivatives, Fair Value [Line Items]
Notional Amount	1,058,779	1,191,621
Asset	12,949	34,391
Liability	0	0
Not designated as hedging \| Futures contracts
Derivatives, Fair Value [Line Items]
Notional Amount	413,200	375,400
Asset	0	0
Liability	2,999	383
Designated as hedging \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Notional Amount	30,000	30,000
Asset	0	0
Liability	$ 1,481	$ 1,909

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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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=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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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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