Commitments and Financial Instruments with Off-Balance-Sheet Risk (Details) - Standby letters of credit - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Commitments and Financial Instruments with Off-Balance-Sheet Risk
Standby letter of credit outstanding	$ 28,470	$ 26,940
Minimum
Commitments and Financial Instruments with Off-Balance-Sheet Risk
Term of standby letter of credit	6 months
Maximum
Commitments and Financial Instruments with Off-Balance-Sheet Risk
Term of standby letter of credit	1 year