Capitalized Mortgage Servicing Rights - Summary of Capitalized MSRs (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Capitalized Mortgage Servicing Rights
Beginning balance			$ 391,254
Ending balance	$ 376,403		376,403
MSRs
Capitalized Mortgage Servicing Rights
Beginning balance	380,719	$ 394,410	391,254	$ 401,471
Additions	14,476	16,550	41,877	49,416
Amortization	(17,299)	(15,900)	(50,817)	(46,920)
Write-downs and payoffs	(1,493)	(2,857)	(5,911)	(11,764)
Ending balance	376,403	392,203	376,403	392,203
Expected amortization of capitalized MSRs balances
2024 (three months ending 12/31/2024)	17,557		17,557
2025	67,899		67,899
2026	62,456		62,456
2027	57,942		57,942
2028	50,678		50,678
Thereafter	119,871		119,871
Total	376,403		376,403
Originated
Capitalized Mortgage Servicing Rights
Beginning balance	374,159	383,267	382,582	386,878
Additions	14,476	16,550	41,877	49,416
Amortization	(16,621)	(14,988)	(48,593)	(43,866)
Write-downs and payoffs	(1,469)	(2,400)	(5,321)	(9,999)
Ending balance	370,545	382,429	370,545	382,429
Acquired
Capitalized Mortgage Servicing Rights
Beginning balance	6,560	11,143	8,672	14,593
Amortization	(678)	(912)	(2,224)	(3,054)
Write-downs and payoffs	(24)	(457)	(590)	(1,765)
Ending balance	$ 5,858	$ 9,774	$ 5,858	$ 9,774

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Amount of write-downs and payoffs applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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.

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

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