Securities - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($) security	Sep. 30, 2019 USD ($) security	Dec. 31, 2018 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Number of securities holdings | security	0	0	0
Shareholders' equity percentage (greater than)	10.00%	10.00%	10.00%
Tax provision related to net realized gains	$ 0	$ 31
Collateral Pledged
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, trading, restricted	$ 257,233	$ 257,233	$ 290,717