Mortgage Servicing Rights, Net - Summary of Changes in the Carrying Amount of Mortgage Servicing Rights (Details) - Mortgage Servicing Rights - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Mortgage Servicing Rights
Beginning Balance	$ 577,948	$ 544,725	$ 563,488	$ 528,983
Additions	26,752	28,246	98,378	98,820
Amortization	(29,793)	(28,760)	(86,959)	(83,592)
Ending Balance	574,907	544,211	574,907	544,211
Valuation Allowance
Beginning Balance	(9,268)	(18,319)	(13,186)	(34,254)
Decrease (increase)	321	8,031	4,239	23,966
Ending Balance	(8,947)	(10,288)	(8,947)	(10,288)
Net Balance	$ 565,960	$ 533,923	$ 565,960	$ 533,923

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122739-111746

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

+ Details

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Balance Type:	debit
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- Definition

Amount of amortization of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Namespace Prefix:	us-gaap_
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- Definition

Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss.

+ References

+ Details

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- Definition

The net increase (decrease) in the valuation allowance for servicing assets subsequently measured using the amortization method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122739-111746

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Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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