Disclosure About Fair Values of Financial Instruments - Summary of Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financial Assets:
Interest-bearing deposits with banks	$ 391,362	$ 725,343
Federal funds sold	5,331	10,974
Investment securities available-for-sale	2,461,644	2,368,592
Derivative assets	66,333	257,137
Other assets	410,152	512,244
Financial Liabilities:
Advances from FHLB	100,000	100,000
Senior debt	49,955	49,938
Subordinated debt	183,032	182,712
Junior subordinated debentures	37,351	37,445
Notes payable	2,102	2,078
Derivative liabilities	19,543	11,211
Level 1
Financial Assets:
Cash and due from banks	212,658	252,447
Interest-bearing deposits with banks	391,362	725,343
Federal funds sold	5,331	10,974
Equity securities with readily determinable fair values not held for trading	1,529	1,862
Level 2
Financial Assets:
Investment securities available-for-sale	2,461,644	2,368,592
Loans held for sale	38,221	87,649
Derivative assets	66,333	257,137
Financial Liabilities:
Deposits	14,499,103	14,753,192
Advances from FHLB	100,000	100,000
Senior debt	51,313	51,202
Subordinated debt	187,781	189,386
Junior subordinated debentures	45,728	48,012
Notes payable	2,102	2,078
Derivative liabilities	19,543	11,211
Level 3
Financial Assets:
Net loans	13,030,957	12,755,360
Other assets	83,225	72,719
Carrying Value
Financial Assets:
Cash and due from banks	212,658	252,447
Interest-bearing deposits with banks	391,362	725,343
Federal funds sold	5,331	10,974
Investment securities available-for-sale	2,461,644	2,368,592
Equity securities with readily determinable fair values not held for trading	1,529	1,862
Loans held for sale	38,221	87,649
Net loans	13,146,945	12,864,012
Derivative assets	66,333	257,137
Other assets	83,225	72,719
Financial Liabilities:
Deposits	14,489,505	14,742,794
Advances from FHLB	100,000	100,000
Senior debt	49,955	49,938
Subordinated debt	183,032	182,712
Junior subordinated debentures	37,351	37,445
Notes payable	2,102	2,078
Derivative liabilities	19,543	11,211
Fair Value
Financial Assets:
Cash and due from banks	212,658	252,447
Interest-bearing deposits with banks	391,362	725,343
Federal funds sold	5,331	10,974
Investment securities available-for-sale	2,461,644	2,368,592
Equity securities with readily determinable fair values not held for trading	1,529	1,862
Loans held for sale	38,221	87,649
Net loans	13,030,957	12,755,360
Derivative assets	66,333	257,137
Other assets	83,225	72,719
Financial Liabilities:
Deposits	14,499,103	14,753,192
Advances from FHLB	100,000	100,000
Senior debt	51,313	51,202
Subordinated debt	187,781	189,386
Junior subordinated debentures	45,728	48,012
Notes payable	2,102	2,078
Derivative liabilities	$ 19,543	$ 11,211