Offsetting Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Securities Borrowed [Abstract]
Gross Amounts of Recognized Assets	$ 140,860	$ 83,619
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Assets Presented in the Statement of Financial Position	140,860	83,619
Financial Instruments	0	0
Cash Collateral Pledged	140,860	83,619
Net Amount	0	0
Securities Loaned [Abstract]
Gross Amounts of Recognized Liabilities	36,894	65,101
Gross Amounts Offset in the Statement of Financial Position	0	0
Net Amounts of Liabilities Presented in the Statement of Financial Position	36,894	65,101
Financial Instruments	0	0
Cash Collateral Received	36,894	65,101
Net Amount	$ 0	$ 0