Condensed Consolidated Balance Sheets [Parenthetical] (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Available-for-sale Securities Pledged as Collateral (in dollars)	$ 600,419,826	$ 366,103,204
Preferred Stock, Par Value (in dollars per share)	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	50,000,000us-gaap_PreferredStockSharesAuthorized	50,000,000us-gaap_PreferredStockSharesAuthorized
Preferred Stock, Dividend Rate, Percentage	8.75%	8.75%
Preferred Stock, Liquidation Preference, Value (in dollars)	25	25
Preferred Stock, Shares Issued	1,610,000us-gaap_PreferredStockSharesIssued	1,610,000us-gaap_PreferredStockSharesIssued
Preferred Stock, Shares Outstanding	1,610,000us-gaap_PreferredStockSharesOutstanding	1,610,000us-gaap_PreferredStockSharesOutstanding
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	450,000,000us-gaap_CommonStockSharesAuthorized	450,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	14,718,750us-gaap_CommonStockSharesIssued	14,718,750us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	14,718,750us-gaap_CommonStockSharesOutstanding	14,718,750us-gaap_CommonStockSharesOutstanding
Variable Interest Entity, Consolidated, Carrying Amount, Assets	2,235,029,892	2,389,784,101
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	$ 2,030,674,136	$ 2,180,936,221

The fair value of available-for-sale securities that serve as collateral for borrowings.

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