Schedule of Mortgage Backed Securities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Schedule Of Investment Income Reported Amounts By Category [Line Items]
TBA dollar roll securities - Face	$ 600,000
TBA dollar roll securities - Cost	632,270
TBA dollar roll securities - Fair Market Value	627,187
TBA dollar roll securities - Net Liability	$ 5,083