Securities, Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Available-for-sale, amortized cost [Abstract]
Due in one year or less	$ 68,479
Due after one through five years	154,511
Due after five through ten years	63,044
Due after ten years	86,590
U.S. government sponsored agency mortgage-backed securities	226,794
Amortized cost	599,418	$ 568,381
CRA investment funds	25,000
Amortized cost	624,418	593,381
Available-for-sale, fair value [Abstract]
Due in one year or less	68,576
Due after one through five years	156,366
Due after five through ten years	65,336
Due after ten years	88,008
U.S. government sponsored agency mortgage-backed securities	227,771
Total debt securities	606,057	570,185
CRA investment funds	25,144
Total securities	631,201	594,936
Held-to-maturity, amortized cost [Abstract]
Due in one year or less	0
Due after one through five years	1,181
Due after five through ten years	0
Due after ten years	0
U.S. government sponsored agency mortgage-backed securities	0
Amortized cost	1,181	1,661
CRA investment funds	0
Total securities	1,181
Held-to-maturity, fair value [Abstract]
Due in one year or less	0
Due after one through five years	1,182
Due after five through ten years	0
Due after ten years	0
U.S. government sponsored agency mortgage-backed securities	0
Total debt securities	1,182	$ 1,651
CRA investment funds	0
Total securities	$ 1,182