Investments - Investments with Unrealized Losses Policy (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Fair Value
Unrealized loss position, Fair Value, Less than 12 Months	$ 24,547	$ 21,710
Unrealized loss position, Fair Value, 12 Months or Longer	2,411	11,459
Unrealized loss position, Fair Value	26,958	33,169
Unrealized Losses
Unrealized loss position, Unrealized losses, Less than 12 Months	(308)	(197)
Unrealized loss position, Unrealized losses, 12 Months or Longer	(22)	(146)
Unrealized losses	(330)	(343)
U.S. agency securities
Fair Value
Unrealized loss position, Fair Value, Less than 12 Months		2,977
Unrealized loss position, Fair Value, 12 Months or Longer		0
Unrealized loss position, Fair Value		2,977
Unrealized Losses
Unrealized loss position, Unrealized losses, Less than 12 Months		(15)
Unrealized loss position, Unrealized losses, 12 Months or Longer		0
Unrealized losses		(15)
Corporate securities
Fair Value
Unrealized loss position, Fair Value, Less than 12 Months	7,729	1,993
Unrealized loss position, Fair Value, 12 Months or Longer	0	0
Unrealized loss position, Fair Value	7,729	1,993
Unrealized Losses
Unrealized loss position, Unrealized losses, Less than 12 Months	(151)	(7)
Unrealized loss position, Unrealized losses, 12 Months or Longer	0	0
Unrealized losses	(151)	(7)
Municipal bonds
Fair Value
Unrealized loss position, Fair Value, Less than 12 Months	10,285
Unrealized loss position, Fair Value, 12 Months or Longer	0
Unrealized loss position, Fair Value	10,285
Unrealized Losses
Unrealized loss position, Unrealized losses, Less than 12 Months	(131)
Unrealized loss position, Unrealized losses, 12 Months or Longer	0
Unrealized losses	(131)
Mortgage-backed securities
Fair Value
Unrealized loss position, Fair Value, Less than 12 Months	4,578	12,345
Unrealized loss position, Fair Value, 12 Months or Longer	2,411	11,459
Unrealized loss position, Fair Value	6,989	23,804
Unrealized Losses
Unrealized loss position, Unrealized losses, Less than 12 Months	(19)	(154)
Unrealized loss position, Unrealized losses, 12 Months or Longer	(22)	(146)
Unrealized losses	(41)	(300)
U.S. Small Business Administration securities
Fair Value
Unrealized loss position, Fair Value, Less than 12 Months	1,955	4,395
Unrealized loss position, Fair Value, 12 Months or Longer	0	0
Unrealized loss position, Fair Value	1,955	4,395
Unrealized Losses
Unrealized loss position, Unrealized losses, Less than 12 Months	(7)	(21)
Unrealized loss position, Unrealized losses, 12 Months or Longer	0	0
Unrealized losses	$ (7)	$ (21)