Fair Value Information - Estimated Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Assets
Total cash and cash equivalents	$ 696,709	$ 1,732,548
Investment securities available-for-sale	3,626,157	3,183,923
Investment securities held-to-maturity	2,412,308	1,925,970
Total loans, net of allowance for loan losses	8,612,007	7,822,694
Deposits:
Interest-bearing	5,190,996	4,872,386
Junior subordinated debentures	0	0
Swaps	503,411	656,551
Carrying Value [Member]
Assets
Total cash and cash equivalents	696,709	1,732,548
Interest-earning balances due from depository institutions	7,382	25,999
Investment securities available-for-sale	3,626,157	3,183,923
Investment securities held-to-maturity	2,412,308	1,925,970
Total loans, net of allowance for loan losses	8,612,007	7,822,694
Interest rate swaps, assets	582	14,163
Deposits:
Interest-bearing	5,190,996	4,872,386
Borrowings	502,829	644,669
Junior subordinated debentures	0	0
Swaps	582	14,163
Estimated Fair Value [Member]
Assets
Total cash and cash equivalents	696,709	1,732,548
Interest-earning balances due from depository institutions	7,382	25,999
Investment securities available-for-sale	3,626,157	3,183,923
Investment securities held-to-maturity	2,134,183	1,921,693
Total loans, net of allowance for loan losses	8,102,801	7,696,210
Interest rate swaps, assets	582	14,163
Deposits:
Interest-bearing	5,186,166	4,871,531
Borrowings	426,427	586,645
Junior subordinated debentures	0	0
Swaps	582	14,163
Estimated Fair Value [Member] \| Level 1 [Member]
Assets
Total cash and cash equivalents	696,709	1,732,548
Interest-earning balances due from depository institutions		0
Investment securities available-for-sale		0
Investment securities held-to-maturity		0
Total loans, net of allowance for loan losses		0
Interest rate swaps, assets		0
Deposits:
Interest-bearing		0
Borrowings		0
Junior subordinated debentures	0	0
Swaps		0
Estimated Fair Value [Member] \| Level 2 [Member]
Assets
Total cash and cash equivalents		0
Interest-earning balances due from depository institutions	7,382	25,999
Investment securities available-for-sale	3,626,157	3,183,923
Investment securities held-to-maturity	2,134,183	1,921,693
Total loans, net of allowance for loan losses		0
Interest rate swaps, assets	582	14,163
Deposits:
Interest-bearing	5,186,166	4,871,531
Borrowings	426,427	586,645
Junior subordinated debentures	0	0
Swaps	582	14,163
Estimated Fair Value [Member] \| Level 3 [Member]
Assets
Total cash and cash equivalents		0
Interest-earning balances due from depository institutions		0
Investment securities available-for-sale		0
Investment securities held-to-maturity		0
Total loans, net of allowance for loan losses	8,102,801	7,696,210
Interest rate swaps, assets		0
Deposits:
Interest-bearing		0
Borrowings		0
Junior subordinated debentures	0	0
Swaps		$ 0

Amount of 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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