Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Fair value of available-for-sale debt securities maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Fair value of available-for-sale debt securities maturing after the tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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Fair value of available-for-sale debt securities maturing in the sixth through tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Fair value of available-for-sale debt securities maturing in the second through fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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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.

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REAL ESTATE SECURITIES - Securities by Remaining Maturity (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Within 1 year	$ 509,276,000		$ 509,276,000		$ 612,752,000
1-5 years	1,633,997,000		1,633,997,000		1,260,381,000
5-10 years	499,779,000		499,779,000		533,604,000
After 10 years	7,907,000		7,907,000		480,000
Fair value of real estate securities	2,650,959,000		2,650,959,000		2,407,217,000
Other than temporary impairments included in consolidated statements of income	0	$ (200,000)	(600,000)	$ (1,600,000)
CMBS
Schedule of Available-for-sale Securities [Line Items]
Within 1 year	508,575,000		508,575,000		610,526,000
1-5 years	1,262,248,000		1,262,248,000		891,752,000
5-10 years	470,570,000		470,570,000		489,228,000
After 10 years	0		0		0
Fair value of real estate securities	2,241,393,000		2,241,393,000		1,991,506,000
CMBS interest-only
Schedule of Available-for-sale Securities [Line Items]
Within 1 year	5,000		5,000		0
1-5 years	347,362,000		347,362,000		344,423,000
5-10 years	0		0		0
After 10 years	0		0		0
Fair value of real estate securities	347,367,000		347,367,000		344,423,000
GNMA interest-only
Schedule of Available-for-sale Securities [Line Items]
Within 1 year	5,000		5,000		6,000
1-5 years	18,072,000		18,072,000		17,159,000
5-10 years	1,099,000		1,099,000		8,549,000
After 10 years	180,000		180,000		480,000
Fair value of real estate securities	19,356,000		19,356,000		26,194,000
Agency securities
Schedule of Available-for-sale Securities [Line Items]
Within 1 year	0		0
1-5 years	830,000		830,000
5-10 years	0		0
After 10 years	0		0
Fair value of real estate securities	830,000		830,000
GNMA construction securities
Schedule of Available-for-sale Securities [Line Items]
Within 1 year					0
1-5 years					386,000
5-10 years					28,253,000
After 10 years					0
Fair value of real estate securities					28,639,000
GNMA permanent securities
Schedule of Available-for-sale Securities [Line Items]
Within 1 year	691,000		691,000		2,220,000
1-5 years	5,485,000		5,485,000		6,661,000
5-10 years	28,110,000		28,110,000		7,574,000
After 10 years	7,727,000		7,727,000		0
Fair value of real estate securities	$ 42,013,000		$ 42,013,000		$ 16,455,000