Fair Value Measurement - Estimates Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Financial Assets
Cash and due from banks	$ 450,009	$ 1,251,358
Equity securities	11,413	13,466
Available-for-sale debt securities	2,884,651	3,013,462
Net held-to-maturity debt securities	1,281,030	1,004,555
Loans held for sale	17,560	25,277
Accrued interest receivable	61,918	60,844
Financial Liabilities
Deposits	13,569,302	13,565,863
Federal Home Loan Bank borrowings	122,650	183,920
Other borrowings	147,964	141,893
Subordinated debt and junior subordinated debt	280,910	132,860
Accrued interest payable	2,815	1,901
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Assets
Cash and due from banks	450,009	1,251,358
Equity securities	11,413	13,466
Accrued interest receivable	61,918	60,844
Financial Liabilities
Deposits	12,463,997	12,273,211
Other borrowings	132,138	134,288
Accrued interest payable	2,815	1,901
Significant Other Observable Inputs (Level 2) [Member]
Financial Assets
Available-for-sale debt securities	2,883,425	3,011,969
Net held-to-maturity debt securities	1,153,244	1,028,047
Loans held for sale	17,560	25,277
Other assets - interest rate swaps	46,815	24,867
Financial Liabilities
Deposits	1,111,718	1,302,266
Federal Home Loan Bank borrowings	121,881	185,684
Subordinated debt and junior subordinated debt	273,599	109,186
Other liabilities - interest rate swaps	45,734	26,388
Significant Unobservable Inputs (Level 3) [Member]
Financial Assets
Available-for-sale debt securities	1,226	1,493
Net held-to-maturity debt securities	350	405
Net loans	9,236,728	9,385,917
Financial Liabilities
Subordinated debt and junior subordinated debt
Carrying Amount [Member]
Financial Assets
Cash and due from banks	450,009	1,251,358
Equity securities	11,413	13,466
Available-for-sale debt securities	2,884,651	3,013,462
Net held-to-maturity debt securities	1,281,030	1,004,555
Net loans	10,091,286	9,611,856
Loans held for sale	17,560	25,277
Other assets - interest rate swaps	46,815	24,867
Accrued interest receivable	61,918	60,844
Financial Liabilities
Deposits	13,569,302	13,565,863
Federal Home Loan Bank borrowings	122,650	183,920
Other borrowings	147,964	141,893
Subordinated debt and junior subordinated debt	280,910	132,860
Other liabilities - interest rate swaps	45,734	26,388
Accrued interest payable	2,815	1,901
Fair Value Estimate [Member]
Financial Assets
Cash and due from banks	450,009	1,251,358
Equity securities	11,413	13,466
Available-for-sale debt securities	2,884,651	3,013,462
Net held-to-maturity debt securities	1,153,594	1,028,452
Net loans	9,236,728	9,385,917
Loans held for sale	17,560	25,277
Other assets - interest rate swaps	46,815	24,867
Accrued interest receivable	61,918	60,844
Financial Liabilities
Deposits	13,575,715	13,575,477
Federal Home Loan Bank borrowings	121,881	185,684
Other borrowings	132,138	134,288
Subordinated debt and junior subordinated debt	273,599	109,186
Other liabilities - interest rate swaps	45,734	26,388
Accrued interest payable	$ 2,815	$ 1,901