Short-Term Borrowings and Long-Term FHLB Advances - Information Concerning Short-term Borrowings (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Long-term Federal Home Loan Bank Advances [Abstract]
Balance at period-end	$ 207,828	$ 227,059	$ 207,828	$ 227,059	$ 252,367
Maximum amount outstanding at any month end	207,828	279,525	207,828	279,525
Average balance outstanding during the period	$ 68,529	$ 218,566	$ 112,844	$ 198,079
Weighted-average interest rate:
As of the period-end (as a percent)	2.33%	1.89%	2.33%	1.89%
Paid during the period (as a percent)	2.09%	1.92%	2.32%	1.72%