Fair Value Measurements - Schedule of Carrying Amount and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financial Assets:
FHLB and other stock	$ 19,044	$ 33,695
Financial Liabilities:
Time deposits	699,166	675,014
Fed funds purchased and securities sold under agreements to repurchase	50,889	60,346
Other borrowings	325,000	658,100
Trust preferred debentures	17,120	17,035
Level 1
Financial Assets:
Cash and cash equivalents	479,126	137,982
FHLB and other stock	0	0
Accrued interest receivable	0	0
Loans/leases, net	0	0
Financial Liabilities:
Time deposits	0	0
Other deposits	0	0
Fed funds purchased and securities sold under agreements to repurchase	0	0
Other borrowings	0	0
Trust preferred debentures	0	0
Accrued interest payable	0	0
Level 2
Financial Assets:
Cash and cash equivalents	0	0
FHLB and other stock	19,044	33,695
Accrued interest receivable	35,611	19,293
Loans/leases, net	2,560	14,050
Financial Liabilities:
Time deposits	707,732	677,205
Other deposits	5,678,355	4,537,907
Fed funds purchased and securities sold under agreements to repurchase	50,889	60,346
Other borrowings	335,868	659,895
Trust preferred debentures	20,888	21,904
Accrued interest payable	1,995	2,486
Level 3
Financial Assets:
Cash and cash equivalents	0	0
FHLB and other stock	0	0
Accrued interest receivable	0	0
Loans/leases, net	5,345,577	4,784,218
Financial Liabilities:
Time deposits	0	0
Other deposits	0	0
Fed funds purchased and securities sold under agreements to repurchase	0	0
Other borrowings	0	0
Trust preferred debentures	0	0
Accrued interest payable	0	0
Carrying Amount
Financial Assets:
Cash and cash equivalents	479,126	137,982
FHLB and other stock	19,044	33,695
Accrued interest receivable	35,611	19,293
Loans/leases, net	5,372,203	4,877,658
Financial Liabilities:
Time deposits	699,166	675,014
Other deposits	5,678,355	4,537,907
Fed funds purchased and securities sold under agreements to repurchase	50,889	60,346
Other borrowings	325,000	658,100
Trust preferred debentures	17,120	17,035
Accrued interest payable	1,995	2,486
Fair Value
Financial Assets:
Cash and cash equivalents	479,126	137,982
FHLB and other stock	19,044	33,695
Accrued interest receivable	35,611	19,293
Loans/leases, net	5,348,137	4,798,268
Financial Liabilities:
Time deposits	707,732	677,205
Other deposits	5,678,355	4,537,907
Fed funds purchased and securities sold under agreements to repurchase	50,889	60,346
Other borrowings	335,868	659,895
Trust preferred debentures	20,888	21,904
Accrued interest payable	$ 1,995	$ 2,486