Deposits - Schedule of Deposit Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Banking and Thrift [Abstract]
Less than one year	$ 743,577	$ 669,610
More than one years to two years	488,016	474,475
More than two years to three years	184,860	169,069
More than three years to four years	40,999	68,184
More than four years	15,072	22,544
Total term certificate accounts	$ 1,472,524	$ 1,403,882