Fair Value Measurement and Fair Value of Financial Instruments - Schedule Of The Carrying And Fair Value Estimates Per The Fair Value Hierarchy Of Financial Instruments Measured On a Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial assets:
Cash and cash equivalents	$ 4,860,073	$ 4,614,984
Interest-bearing deposits with banks	116,101	10,498
Resale agreements	425,000	785,000
HTM debt securities	2,928,399	2,956,040
Restricted equity securities, at cost	164,908	79,811
Loans held-for-investment, net	52,556,696	51,542,039
Financial liabilities:
Federal Home Loan Bank (“FHLB”) advances	3,500,000	0
Carrying Amount
Financial assets:
Cash and cash equivalents	4,860,073	4,614,984
Interest-bearing deposits with banks	116,101	10,498
Resale agreements	425,000	785,000
HTM debt securities	2,928,399	2,956,040
Restricted equity securities, at cost	164,908	79,811
Loans held-for-sale		116
Loans held-for-investment, net	52,556,696	51,542,039
Mortgage servicing rights	5,563	6,602
Accrued interest receivable	323,788	331,490
Financial liabilities:
Demand, checking, savings and money market deposits	38,483,004	38,048,974
Time deposits	23,217,111	18,043,464
Federal Home Loan Bank (“FHLB”) advances	3,500,000
BTFP borrowings		4,500,000
Long-term debt	31,923	148,249
Accrued interest payable	64,151	205,430
Estimated Fair Value
Financial assets:
Cash and cash equivalents	4,860,073	4,614,984
Interest-bearing deposits with banks	116,101	10,498
Resale agreements	350,151	699,056
HTM debt securities	2,510,352	2,453,971
Restricted equity securities, at cost	164,908	79,811
Loans held-for-sale		116
Loans held-for-investment, net	51,255,590	50,256,565
Mortgage servicing rights	9,416	9,470
Accrued interest receivable	323,788	331,490
Financial liabilities:
Demand, checking, savings and money market deposits	38,483,004	38,048,974
Time deposits	23,220,896	18,004,951
Federal Home Loan Bank (“FHLB”) advances	3,504,340
BTFP borrowings		4,500,000
Long-term debt	30,334	150,896
Accrued interest payable	64,151	205,430
Estimated Fair Value | Level 1
Financial assets:
Cash and cash equivalents	4,860,073	4,614,984
Interest-bearing deposits with banks	0	0
Resale agreements	0	0
HTM debt securities	505,144	488,551
Restricted equity securities, at cost	0	0
Loans held-for-sale		0
Loans held-for-investment, net	0	0
Mortgage servicing rights	0	0
Accrued interest receivable	0	0
Financial liabilities:
Demand, checking, savings and money market deposits	0	0
Time deposits	0	0
Federal Home Loan Bank (“FHLB”) advances	0
BTFP borrowings		0
Long-term debt	0	0
Accrued interest payable	0	0
Estimated Fair Value | Level 2
Financial assets:
Cash and cash equivalents	0	0
Interest-bearing deposits with banks	116,101	10,498
Resale agreements	350,151	699,056
HTM debt securities	2,005,208	1,965,420
Restricted equity securities, at cost	164,908	79,811
Loans held-for-sale		116
Loans held-for-investment, net	0	0
Mortgage servicing rights	0	0
Accrued interest receivable	323,788	331,490
Financial liabilities:
Demand, checking, savings and money market deposits	38,483,004	38,048,974
Time deposits	23,220,896	18,004,951
Federal Home Loan Bank (“FHLB”) advances	3,504,340
BTFP borrowings		4,500,000
Long-term debt	30,334	150,896
Accrued interest payable	64,151	205,430
Estimated Fair Value | Level 3
Financial assets:
Cash and cash equivalents	0	0
Interest-bearing deposits with banks	0	0
Resale agreements	0	0
HTM debt securities	0	0
Restricted equity securities, at cost	0	0
Loans held-for-sale		0
Loans held-for-investment, net	51,255,590	50,256,565
Mortgage servicing rights	9,416	9,470
Accrued interest receivable	0	0
Financial liabilities:
Demand, checking, savings and money market deposits	0	0
Time deposits	0	0
Federal Home Loan Bank (“FHLB”) advances	0
BTFP borrowings		0
Long-term debt	0	0
Accrued interest payable	$ 0	$ 0