Derivative Financial Instruments (Details 4) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Offsetting of financial liabilities and derivative liabilities
Gross Amounts of Recognized Liabilities	$ 131,272	$ 138,012
Gross Amounts Offset in the Statement of Financial Position	272	367
Net Amounts of Liabilities Presented in the Statement of Financial Position	131,000	137,645
Gross amounts Not Offset in the Statement of Financial Position
Financial Instruments	122,658	128,343
Cash Collateral Pledged	7,994	9,018
Net Amount	348	284
Interest rate swaps
Offsetting of financial liabilities and derivative liabilities
Gross Amounts of Recognized Liabilities	8,614	9,669
Gross Amounts Offset in the Statement of Financial Position	272	367
Net Amounts of Liabilities Presented in the Statement of Financial Position	8,342	9,302
Gross amounts Not Offset in the Statement of Financial Position
Cash Collateral Pledged	7,994	9,018
Net Amount	348	284
Repurchase agreements
Offsetting of financial liabilities and derivative liabilities
Gross Amounts of Recognized Liabilities	122,658	128,343
Net Amounts of Liabilities Presented in the Statement of Financial Position	122,658	128,343
Gross amounts Not Offset in the Statement of Financial Position
Financial Instruments	$ 122,658	$ 128,343