Repurchase Agreements - Amounts At Risk (Details) (Citigroup Global Markets, Inc., USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Citigroup Global Markets, Inc.
Repurchase Agreement Counterparties With Whom Amount At Risk Exceeds Ten Percent of Stockholders Equity [Line Items]
Amount At Risk	$ 19,074,000	$ 5,487,000
Weighted Average Maturity of Repurchase Agreement in Days	20 days	11 days
Percentage of Stockholders' Equity at Risk	11.00%	12.30%