Parent Company Only Financial Information - Condensed Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Trading securities	$ 9,809	$ 7,786
Total Assets	3,763,659	3,221,521
Liabilities
Subordinated debentures	70,620	70,620
Total liabilities	3,458,693	2,958,691
Total shareholders’ equity	304,966	262,830	$ 243,910	$ 211,784
Total Liabilities and Shareholders’ Equity	3,763,659	3,221,521
Parent Company
Assets
Cash	750	355
Trading securities	683	623
Investment in bank subsidiary	349,307	310,574
Investment in non-bank subsidiaries	24,606	20,686
Deferreds and current receivable	1,576	1,459
Other assets	1,479	1,749
Total Assets	378,401	335,446
Liabilities
Borrowings from subsidiary	850	200
Subordinated debentures	70,620	70,620
Other liabilities	1,965	1,796
Total liabilities	73,435	72,616
Total shareholders’ equity	304,966	262,830
Total Liabilities and Shareholders’ Equity	$ 378,401	$ 335,446