Deposit Accounts The aggregate annual maturities of certificates of deposit accounts (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Balance
Within 3 months	$ 79,798
4 to 6 months	131,699
7 to 12 months	188,046
13 to 24 months	108,194
25 to 36 months	8,365
37 to 60 months	4,237
Over 60 months	636
Total certificates of deposit accounts	$ 520,975	$ 441,673
Weighted Average Interest Rate
Within 3 months (as a percent)	0.55%
4 to 6 months (as a percent)	0.81%
7 to 12 months (as a percent)	0.78%
13 to 24 months (as a percent)	0.98%
25 to 36 months (as a percent)	1.09%
37 to 60 months (as a percent)	1.10%
Over 60 months (as a percent)	0.97%
Total certificates of deposit accounts (as a percent)	0.80%	0.89%