DEBT OBLIGATIONS - Schedule of Debt Obligations (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014
Debt Instrument [Line Items]
Outstanding Face Amount	$ 5,338,807,000
Carrying Value	5,338,807,000		6,062,299,000
Weighted Average Funding Cost	1.90%
Weighted Average Life (Years)	10 months 2 days
Repurchase Agreements [Member] | Agency RMBS [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	1,612,972,000	[1],[2]
Carrying Value	1,612,972,000	[1],[2]	1,707,602,000	[1],[2]
Weighted Average Funding Cost	0.36%	[1],[2]
Weighted Average Life (Years)	26 days	[1],[2]
Repurchase Agreements [Member] | Agency RMBS [Member] | Collateral [Member]
Debt Instrument [Line Items]
Weighted Average Life (Years)	5 years 4 months 21 days	[1],[2]
Outstanding Face Amount of Collateral	1,575,759,000	[1],[2]
Amortized Cost Basis of Collateral	1,659,781,000	[1],[2]
Carrying Value of Collateral	1,664,996,000	[1],[2]
Repurchase Agreements [Member] | Non-Agency RMBS [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	315,919,000	[1],[3]
Carrying Value	315,919,000	[1],[3]	539,049,000	[1],[3]
Weighted Average Funding Cost	1.77%	[1],[3]
Weighted Average Life (Years)	1 month 6 days	[1],[3]
Repurchase Agreements [Member] | Non-Agency RMBS [Member] | Collateral [Member]
Debt Instrument [Line Items]
Weighted Average Life (Years)	9 years 9 days	[1],[3]
Outstanding Face Amount of Collateral	1,500,816,000	[1],[3]
Amortized Cost Basis of Collateral	428,696,000	[1],[3]
Carrying Value of Collateral	439,579,000	[1],[3]
Repurchase Agreements [Member] | Residential Mortgage [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	392,521,000	[1],[4]
Carrying Value	392,521,000	[1],[4]	867,334,000	[1],[4]
Weighted Average Funding Cost	2.37%	[1],[4]
Weighted Average Life (Years)	9 months 7 days	[1],[4]
Repurchase Agreements [Member] | Residential Mortgage [Member] | Collateral [Member]
Debt Instrument [Line Items]
Weighted Average Life (Years)	4 years 7 months 3 days	[1],[4]
Outstanding Face Amount of Collateral	584,085,000	[1],[4]
Amortized Cost Basis of Collateral	514,109,000	[1],[4]
Carrying Value of Collateral	514,109,000	[1],[4]
Repurchase Agreements [Member] | Real Estate Owned [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	17,977,000	[1],[5]
Carrying Value	17,977,000	[1],[5]	35,105,000	[1],[5]
Weighted Average Funding Cost	2.82%	[1],[5]
Weighted Average Life (Years)	1 year 1 month 17 days	[1],[5]
Repurchase Agreements [Member] | Real Estate Owned [Member] | Collateral [Member]
Debt Instrument [Line Items]
Carrying Value of Collateral	33,408,000	[1],[5]
Repurchase Agreements [Member] | Total Repurchase Agreements [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	2,339,389,000	[1]
Carrying Value	2,339,389,000	[1]	3,149,090,000	[1]
Weighted Average Funding Cost	0.91%	[1]
Weighted Average Life (Years)	2 months 12 days	[1]
Notes Payable [Member] | Residential Mortgage [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	23,604,000	[6]
Carrying Value	23,604,000	[6]	22,194,000	[6]
Weighted Average Funding Cost	3.08%	[6]
Weighted Average Life (Years)	6 months 19 days	[6]
Notes Payable [Member] | Residential Mortgage [Member] | Collateral [Member]
Debt Instrument [Line Items]
Weighted Average Life (Years)	4 years 15 days	[6]
Outstanding Face Amount of Collateral	42,306,000	[6]
Amortized Cost Basis of Collateral	25,013,000	[6]
Carrying Value of Collateral	23,294,000	[6]
Notes Payable [Member] | Real Estate Owned [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	402,000	[6]
Carrying Value	402,000	[6]	785,000	[6]
Weighted Average Funding Cost	3.08%	[6]
Weighted Average Life (Years)	6 months 19 days	[6]
Notes Payable [Member] | Real Estate Owned [Member] | Collateral [Member]
Debt Instrument [Line Items]
Carrying Value of Collateral	397,000	[6]
Notes Payable [Member] | Secured Corporate Loan [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	100,000,000	[7]
Carrying Value	100,000,000	[7]	0	[7]
Weighted Average Funding Cost	3.93%	[7]
Weighted Average Life (Years)	3 months 26 days	[7]
Notes Payable [Member] | Secured Corporate Loan [Member] | Collateral [Member]
Debt Instrument [Line Items]
Weighted Average Life (Years)	5 years 4 months 4 days	[7]
Outstanding Face Amount of Collateral	105,939,876,000	[7]
Amortized Cost Basis of Collateral	239,540,000	[7]
Carrying Value of Collateral	279,404,000	[7]
Notes Payable [Member] | Servicer Advances [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	2,875,412,000	[8]
Carrying Value	2,875,412,000	[8]	2,890,230,000	[8]
Weighted Average Funding Cost	2.62%	[8]
Weighted Average Life (Years)	1 year 4 months 17 days	[8]
Notes Payable [Member] | Servicer Advances [Member] | Collateral [Member]
Debt Instrument [Line Items]
Weighted Average Life (Years)	3 years 11 months 10 days	[8]
Outstanding Face Amount of Collateral	3,068,306,000	[8]
Amortized Cost Basis of Collateral	3,168,909,000	[8]
Carrying Value of Collateral	3,245,457,000	[8]
Notes Payable [Member] | Total Notes Payable [Member]
Debt Instrument [Line Items]
Outstanding Face Amount	2,999,418,000
Carrying Value	$ 2,999,418,000		$ 2,913,209,000
Weighted Average Funding Cost	2.66%
Weighted Average Life (Years)	1 year 4 months 2 days

[1] These repurchase agreements had approximately $2.0 million of associated accrued interest payable as of March 31, 2015.

[2] The counterparties of these repurchase agreements are Mizuho ($89.6 million), Morgan Stanley ($73.3 million), Barclays ($788.7 million), Daiwa ($338.9 million) and Jefferies ($322.5 million) and were subject to customary margin call provisions.

[3] The counterparties of these repurchase agreements are Barclays ($5.6 million), Credit Suisse ($107.3 million), Royal Bank of Canada ($10.2 million), Bank of America, N.A. ($80.1 million), Goldman Sachs ($60.9 million) and UBS ($51.8 million) and were subject to customary margin call provisions. All of the Non-Agency repurchase agreements have LIBOR-based floating interest rates.

[4] The counterparties on these repurchase agreements are Bank of America N.A. ($39.5 million maturing in August 2016), Nomura ($68.7 million maturing in May 2016), Citibank ($4.8 million maturing in May 2015) and Credit Suisse ($279.5 million maturing in November 2015). All of these repurchase agreements have LIBOR-based floating interest rates.

[5] The counterparties of these repurchase agreements are Credit Suisse ($1.2 million), Bank of America, N.A. ($2.0 million), Citibank ($0.4 million) and Nomura ($14.4 million). All of these repurchase agreements have LIBOR-based floating interest rates.

[6] The note is payable to Nationstar and bears interest equal to one-month LIBOR plus 2.875%.

[7] The loan bears interest equal to the sum of (i) a floating rate index equal to one-month LIBOR and (ii) a margin of 3.75%. The outstanding face of the collateral represents the UPB of the residential mortgage loans underlying the Excess MSRs that secure this corporate loan.

[8] $0.7 billion face amount of the notes have a fixed rate while the remaining notes bear interest equal to the sum of (i) a floating rate index rate equal to one-month LIBOR or a cost of funds rate, as applicable, and (ii) a margin ranging from 1.9% to 2.0%.