Offsetting Assets and Liabilities Offsetting Assets (Details) - USD ($) $ in Thousands		Mar. 31, 2016	Dec. 31, 2015
Offsetting Assets [Line Items]
Derivative assets, fair value, gross asset		$ 14,845	$ 7,835
Derivative assets, fair value, gross liability		0	0
Derivative assets, fair value, amount not offset against collateral		14,845	7,835
Derivative assets, gross amount not offset in the balance sheet, financial instruments received as collateral	[1]	(14,845)	(7,835)
Derivative assets, gross amounts not offset in the balance sheet, cash received as collateral	[1]	0	0
Derivative assets, fair value, net amount offset against collateral		$ 0	$ 0

[1] Amount disclosed for collateral received by or posted to the same counterparty include cash and the fair value of MBS up to and not exceeding the net amount of the asset or liability presented in the balance sheet. The fair value of the actual collateral received by or posted to the same counterparty may exceed the amounts presented.