Investments - Realized Gains (Losses) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Proceeds from Sale and Maturity of Debt Securities, Available-for-sale [Abstract]
Proceeds from sales, calls and maturities of securities available for sale		$ 4,255	$ 11,137	$ 30,895	$ 13,447
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract]
Gross gains on sales, calls and maturities of securities available for sale			20	128	21
Gross losses on sales, calls and maturities of securities available for sale			(19)	(99)	(19)
Net gains on sale of securities available for sale	[1]		$ 1	$ 29	$ 2

[1] Not within scope of ASC 606. Revenue streams are not related to contract with customers and are accounted for on an accrual basis under other provisions of GAAP