Loans - Ratings (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($)
Investments in loans
Total gross loans	$ 5,956,062	$ 6,269,546
Total gross loans (as a percent)	100.00%	100.00%
Number of impaired individual mortgage loans held-for-investment \| loan	0
Amount of loan impairment charges on individual loans held-for-investment	$ 0
Rating 1
Investments in loans
Total gross loans	$ 921	$ 664
Rating 1 \| Maximum
Investments in loans
LTV (as a percent)	65.00%
Rating 2
Investments in loans
Total gross loans	$ 1,349,603	$ 675,678
Total gross loans (as a percent)	22.60%	10.80%
Rating 2 \| Maximum
Investments in loans
LTV (as a percent)	70.00%
Rating 3
Investments in loans
Total gross loans	$ 4,025,809	$ 4,987,459
Total gross loans (as a percent)	67.60%	79.60%
Rating 3 \| Maximum
Investments in loans
LTV (as a percent)	80.00%
Rating 4
Investments in loans
Total gross loans	$ 458,133	$ 401,880
Total gross loans (as a percent)	7.70%	6.40%
Allowance for loan losses as a percent of carrying amount	1.50%
Rating 4 \| Minimum
Investments in loans
LTV (as a percent)	80.00%
Rating 4 \| Maximum
Investments in loans
LTV (as a percent)	90.00%
Rating 5
Investments in loans
Total gross loans	$ 58,317
Total gross loans (as a percent)	1.00%
Allowance for loan losses as a percent of carrying amount	5.00%
Rating 5 \| Minimum
Investments in loans
LTV (as a percent)	90.00%
N/A
Investments in loans
Total gross loans	$ 63,279	$ 203,865
Total gross loans (as a percent)	1.10%	3.20%
First Mortgages, excluding Cost Recovery Loans \| Investment and Servicing Segment
Investments in loans
Carrying amount of loans 90 days or more past due	$ 151,000
Mezzanine Loans \| Investment and Servicing Segment
Investments in loans
Carrying amount of loans 90 days or more past due	58,100
Total loans held-for-investment
Investments in loans
Total gross loans	5,857,783	$ 5,979,108
Total loans held-for-investment \| First Mortgages, excluding Cost Recovery Loans
Investments in loans
Total gross loans	4,865,994	4,723,852
Total loans held-for-investment \| First Mortgages, excluding Cost Recovery Loans \| Rating 1
Investments in loans
Total gross loans	921	664
Total loans held-for-investment \| First Mortgages, excluding Cost Recovery Loans \| Rating 2
Investments in loans
Total gross loans	1,092,731	496,372
Total loans held-for-investment \| First Mortgages, excluding Cost Recovery Loans \| Rating 3
Investments in loans
Total gross loans	3,348,874	3,979,247
Total loans held-for-investment \| First Mortgages, excluding Cost Recovery Loans \| Rating 4
Investments in loans
Total gross loans	365,151	247,569
Total loans held-for-investment \| First Mortgages, excluding Cost Recovery Loans \| Rating 5
Investments in loans
Total gross loans	58,317
Total loans held-for-investment \| Subordinated mortgages
Investments in loans
Total gross loans	278,032	392,563
Total loans held-for-investment \| Subordinated mortgages \| Rating 2
Investments in loans
Total gross loans	27,069	88,857
Total loans held-for-investment \| Subordinated mortgages \| Rating 3
Investments in loans
Total gross loans	250,963	270,435
Total loans held-for-investment \| Subordinated mortgages \| Rating 4
Investments in loans
Total gross loans		33,271
Total loans held-for-investment \| Mezzanine Loans
Investments in loans
Total gross loans	713,757	862,693
Total loans held-for-investment \| Mezzanine Loans \| Rating 2
Investments in loans
Total gross loans	194,803	90,449
Total loans held-for-investment \| Mezzanine Loans \| Rating 3
Investments in loans
Total gross loans	425,972	651,204
Total loans held-for-investment \| Mezzanine Loans \| Rating 4
Investments in loans
Total gross loans	92,982	121,040
Loans held-for-sale
Investments in loans
Total gross loans	63,279	203,865
Loans held-for-sale \| N/A
Investments in loans
Total gross loans	63,279	203,865
Loans transferred as secured borrowings
Investments in loans
Total gross loans	35,000	86,573
Loans transferred as secured borrowings \| Rating 2
Investments in loans
Total gross loans	$ 35,000
Loans transferred as secured borrowings \| Rating 3
Investments in loans
Total gross loans		$ 86,573

Represents the amount of impairment charges on individual mortgage loans of real estate that are held for investment.

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- Definition

Represents the range of loan to value ratio that is used to classify a loan into a particular credit rating category.

+ References

No definition available.

+ Details

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- Definition

Represents the allowance for loan losses as a percent of carrying amount.

+ References

No definition available.

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- Definition

The gross carrying amount of the outstanding balance due under the mortgage loan.

+ References

No definition available.

+ Details

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- Definition

The gross carrying amount of the outstanding balance due under the mortgage loan as a percentage of total loans.

+ References

No definition available.

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- Definition

Represents the number of impaired individual mortgage loans on real estate that are held for investment.

+ References

No definition available.

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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