Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Investment securities available for sale, amortized cost	$ 956,803	$ 839,192
Investment securities available for sale, allowance for credit losses	156	0
Time deposits	$ 100	$ 100
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	100,000,000	100,000,000
Common stock, issued (in shares)	32,228,636	33,241,496
Common stock, outstanding (in shares)	32,228,636	33,241,496