Investment Securities - Continuous Unrealized Loss (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months	$ 34,504,000		$ 34,504,000		$ 43,337,000
Unrealized loss, less than 12 months	(355,000)		(355,000)		(153,000)
Fair value, 12 months or more	0		0		8,848,000
Unrealized loss, 12 months or more	0		0		(90,000)
Total fair value	34,504,000		34,504,000		52,185,000
Total unrealized loss	(355,000)		(355,000)		(243,000)
OTTI Loss, AFS	0	$ 0	0	$ 0
Sale of certain investments securities			5,100,000
Agency bond securities
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months	29,886,000		29,886,000
Unrealized loss, less than 12 months	(114,000)		(114,000)
Fair value, 12 months or more	0		0
Unrealized loss, 12 months or more	0		0
Total fair value	29,886,000		29,886,000
Total unrealized loss	(114,000)		(114,000)
Agency mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months					43,337,000
Unrealized loss, less than 12 months					(153,000)
Fair value, 12 months or more					8,735,000
Unrealized loss, 12 months or more					(88,000)
Total fair value					52,072,000
Total unrealized loss					(241,000)
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Fair value, less than 12 months	4,618,000		4,618,000		0
Unrealized loss, less than 12 months	(241,000)		(241,000)		0
Fair value, 12 months or more	0		0		113,000
Unrealized loss, 12 months or more	0		0		(2,000)
Total fair value	4,618,000		4,618,000		113,000
Total unrealized loss	$ (241,000)		$ (241,000)		$ (2,000)