Securities Available-for-sale - Investments with Unrealized Losses Policy (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position, Less than 12 Months, Fair Value	$ 44,811	$ 61,123
Unrealized loss position, Less than 12 Months, Unrealized Losses	(499)	(1,037)
Unrealized loss position, 12 Months or Longer, Fair Value	3,111	1,438
Unrealized loss position, 12 Months or Longer, Unrealized Losses	(105)	(62)
Unrealized loss position, Fair Value	47,922	62,561
Unrealized loss position, Unrealized Losses	(604)	(1,099)
U.S. agency securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position, Less than 12 Months, Fair Value	2,025	6,998
Unrealized loss position, Less than 12 Months, Unrealized Losses	(12)	(94)
Unrealized loss position, 12 Months or Longer, Fair Value	0	0
Unrealized loss position, 12 Months or Longer, Unrealized Losses	0	0
Unrealized loss position, Fair Value	2,025	6,998
Unrealized loss position, Unrealized Losses	(12)	(94)
Corporate securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position, Less than 12 Months, Fair Value	2,122	5,048
Unrealized loss position, Less than 12 Months, Unrealized Losses	(6)	(106)
Unrealized loss position, 12 Months or Longer, Fair Value	1,927	1,438
Unrealized loss position, 12 Months or Longer, Unrealized Losses	(69)	(62)
Unrealized loss position, Fair Value	4,049	6,486
Unrealized loss position, Unrealized Losses	(75)	(168)
Municipal bonds
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position, Less than 12 Months, Fair Value	2,443	6,741
Unrealized loss position, Less than 12 Months, Unrealized Losses	(34)	(83)
Unrealized loss position, 12 Months or Longer, Fair Value	0	0
Unrealized loss position, 12 Months or Longer, Unrealized Losses	0	0
Unrealized loss position, Fair Value	2,443	6,741
Unrealized loss position, Unrealized Losses	(34)	(83)
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position, Less than 12 Months, Fair Value	31,393	39,373
Unrealized loss position, Less than 12 Months, Unrealized Losses	(402)	(713)
Unrealized loss position, 12 Months or Longer, Fair Value	1,184	0
Unrealized loss position, 12 Months or Longer, Unrealized Losses	(36)	0
Unrealized loss position, Fair Value	32,577	39,373
Unrealized loss position, Unrealized Losses	(438)	(713)
U.S. Small Business Administration securities
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss position, Less than 12 Months, Fair Value	6,828	2,963
Unrealized loss position, Less than 12 Months, Unrealized Losses	(45)	(41)
Unrealized loss position, 12 Months or Longer, Fair Value	0	0
Unrealized loss position, 12 Months or Longer, Unrealized Losses	0	0
Unrealized loss position, Fair Value	6,828	2,963
Unrealized loss position, Unrealized Losses	$ (45)	$ (41)