Securities, Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Available-for-sale, amortized cost [Abstract]
Due in one year or less	$ 69,861
Due after one through five years	162,304
Due after five through ten years	51,203
Due after ten years	82,849
U.S. government sponsored agency mortgage-backed securities	219,961
Amortized cost	586,178	$ 583,939
CRA investment funds	25,000
Amortized cost	611,178	608,939
Available-for-sale, fair value [Abstract]
Due in one year or less	69,819
Due after one through five years	163,221
Due after five through ten years	52,067
Due after ten years	82,893
U.S. government sponsored agency mortgage-backed securities	217,872
Total debt securities	585,872	581,036
CRA investment funds	24,496
Total securities	610,368	605,394
Held-to-maturity, amortized cost [Abstract]
Due in one year or less	0
Due after one through five years	858
Due after five through ten years	0
Due after ten years	0
U.S. government sponsored agency mortgage-backed securities	0
Amortized cost	858	866
CRA investment funds	0
Total securities	858
Held-to-maturity, fair value [Abstract]
Due in one year or less	0
Due after one through five years	858
Due after five through ten years	0
Due after ten years	0
U.S. government sponsored agency mortgage-backed securities	0
Total debt securities	858	$ 867
CRA investment funds	0
Total securities	$ 858