Derivatives - Gains (Losses) Included in the Consolidated Statements of Income Related to Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derivatives, Fair Value [Line Items]
Net tax expenses (benefits) recognized on net change in unrealized gain (loss) on hedging activities	$ 273	$ 112
Amount of gain recognized in other comprehensive (loss) income, net of tax expense of $273 and $112	774	316
Not designated as hedging \| Mortgage Banking Income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	15,958	5,484
Not designated as hedging \| Interest rate-lock commitments \| Mortgage Banking Income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	(5,446)	(21,442)
Not designated as hedging \| Forward commitments \| Mortgage Banking Income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	37,903	43,258
Not designated as hedging \| Futures contracts \| Mortgage Banking Income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	(16,535)	(16,332)
Not designated as hedging \| Option contracts \| Mortgage Banking Income
Derivatives, Fair Value [Line Items]
Gains (losses) on derivative financial instruments	36	0
Designated as hedging
Derivatives, Fair Value [Line Items]
Amount of gain recognized in other comprehensive (loss) income, net of tax expense of $273 and $112	$ 774	$ 316

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e637-108580

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580

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