Fair Value - Level 3 Unobservable Inputs, Mortgage Loans and IRLC (Details) $ in Thousands	Mar. 31, 2025 USD ($) item	Dec. 31, 2024 USD ($) item
Excess servicing spread financing
Loans held for sale	$ 7,095,270	$ 8,217,468
Mortgage loans held for sale \| Level 3
Excess servicing spread financing
Loans held for sale	$ 441,621	$ 434,053
Mortgage loans held for sale \| Discount rate \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.061	0.065
Mortgage loans held for sale \| Discount rate \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.093	0.093
Mortgage loans held for sale \| Discount rate \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.067	0.07
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.025	0.022
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.031	0.028
Mortgage loans held for sale \| Twelve-month projected housing price index Change \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.027	0.023
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.064	0.064
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.429	0.344
Mortgage loans held for sale \| Prepayment/resale speed \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.261	0.22
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.065	0.065
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Maximum
Excess servicing spread financing
Input	0.484	0.413
Mortgage loans held for sale \| Total prepayment speed \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.285	0.239
Interest rate lock commitments \| Level 3
Excess servicing spread financing
Fair Value	$ 109,942	$ 33,565
Committed amount	$ 9,890,968	$ 7,801,677
Interest rate lock commitments \| Pull-through rate \| Level 3 \| Minimum
Excess servicing spread financing
Input	0.235	0.298
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	0.862	0.882
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Minimum
Excess servicing spread financing
Input \| item	1	1
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Maximum
Excess servicing spread financing
Input \| item	8.7	8.6
Interest rate lock commitments \| Mortgage servicing rights value expressed as servicing fee multiple \| Level 3 \| Weighted average
Excess servicing spread financing
Input \| item	5.3	5.4
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	0.046	0.046
Interest rate lock commitments \| Percentage of unpaid principal balance \| Level 3 \| Weighted average
Excess servicing spread financing
Input	0.023	0.024

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

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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).

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Nominal or face amount used to calculate payment on derivative.

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

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