Warehouse Borrowings - Additional Information (Details) - Warehouse Agreement Borrowings [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Feb. 11, 2017	Dec. 31, 2015
Short-term Debt [Line Items]
Aggregate borrowing capacity	$ 2,500.0
Variable Interest Rate Basis	LIBOR
Maturity/Expiration Date	Feb. 21, 2018
Weighted-average stated interest rate	3.27%		2.83%
Minimum [Member]
Short-term Debt [Line Items]
Interest rate spread	2.10%
Maximum [Member]
Short-term Debt [Line Items]
Interest rate spread	3.13%
Borrowings to fund purchase or origination of residential loans [Member]
Short-term Debt [Line Items]
Days to Transfer Loans	20 days
Borrowings to fund purchase or origination of residential loans [Member] | Minimum [Member]
Short-term Debt [Line Items]
Debt Instrument, Repayment Terms	60 days
Borrowings to fund purchase or origination of residential loans [Member] | Maximum [Member]
Short-term Debt [Line Items]
Debt Instrument, Repayment Terms	90 days
Borrowings to fund repurchase performing HECMs [Member] | Maximum [Member]
Short-term Debt [Line Items]
Debt Instrument, Repayment Terms	364 days
Borrowings to fund repurchase non-performing HECMs [Member] | Minimum [Member]
Short-term Debt [Line Items]
Debt Instrument, Repayment Terms	180 days
Borrowings to fund repurchase non-performing HECMs [Member] | Maximum [Member]
Short-term Debt [Line Items]
Debt Instrument, Repayment Terms	364 days
Residential Mortgage [Member]
Short-term Debt [Line Items]
Warehouse borrowings associated with amount pledged as collateral	$ 1,100.0
Amount Pledged as Collateral	$ 1,200.0
Repurchased HECMs And Real Estate Owned [Member]
Short-term Debt [Line Items]
Maturity/Expiration Date	Feb. 11, 2017
Warehouse borrowings associated with amount pledged as collateral	$ 104.8
Amount Pledged as Collateral	$ 118.3
Repurchased HECMs And Real Estate Owned [Member] | Subsequent Event [Member]
Short-term Debt [Line Items]
Warehouse borrowings associated with amount pledged as collateral		$ 125.0