Fair Value - Level 3 Unobservable Inputs, Mortgage Loans and IRLC (Details) $ in Thousands	Mar. 31, 2024 USD ($) item	Dec. 31, 2023 USD ($) item
Excess servicing spread financing
Loans held for sale	$ 5,200,350	$ 4,420,691
Mortgage loans held for sale \| Level 3
Excess servicing spread financing
Loans held for sale	$ 466,392	$ 478,564
Mortgage loans held for sale \| Discount rate \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.067	0.071
Mortgage loans held for sale \| Discount rate \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.102	0.102
Mortgage loans held for sale \| Discount rate \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.074	0.072
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.018	0.003
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.019	0.005
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.018	0.005
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.062	0.040
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.389	0.369
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.259	0.248
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.063	0.040
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.473	0.503
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.293	0.322
Interest rate lock commitments \| Level 3
Excess servicing spread financing
Fair Value	$ 69,808	$ 89,593
Committed amount	$ 7,270,122	$ 6,349,628
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.196	0.102
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Maximum
Excess servicing spread financing
Input	1	1
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.791	0.811
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Minimum
Excess servicing spread financing
Input \| item	1.1	1.1
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Maximum
Excess servicing spread financing
Input \| item	7.8	7.3
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Weighted average
Excess servicing spread financing
Input \| item	4.4	4.2
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.003	0.003
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.043	0.043
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.021	0.019

The net fair value portion of mortgage loans held-for-sale.

No definition available.

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- Definition

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

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+ References

No definition available.

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- Definition

Value of input used to measure loan, held for sale.

+ References

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- Definition

Fair value portion of mortgage loans held-for-sale.

+ References

No definition available.

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