Other Assets and Liabilities - Additional Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($) Location	Dec. 31, 2015 USD ($) Location	Dec. 31, 2014 USD ($)
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)		$ 5,533	$ 4,896
Amount related to transfers into REO		12,000
REO liquidations		13,000
Unrealized gain on REO from market value adjustments		2,000
Costs incurred and expensed	$ 10,401	10,401	$ 0	$ 0
Other costs		(3,486)
Termination Benefits
Other Assets and Other Liabilities [Line Items]
Costs incurred and expensed	9,000	8,746
Other costs	(3,000)	(3,486)
Contract Termination Costs
Other Assets and Other Liabilities [Line Items]
Costs incurred and expensed	$ 2,000	1,655
Other costs		$ 0
Sequoia Entities
Other Assets and Other Liabilities [Line Items]
Number of REO properties recorded on balance sheet | Location		23	23