Represents the additional percentage points added to the reference rate to compute the variable rate on the debt instrument, in an event of default.

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- Definition

The high end of the range of percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

The low end of the range of percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Represents the period of extension in the term of maturity of borrowings.

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- Definition

Represents the maximum amount of the obligation under the repurchase agreement that is guaranteed by the reporting entity.

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- Definition

Represents the maximum amount of the obligation under the repurchase agreement that is guaranteed by the reporting entity, as a percent of the then currently outstanding repurchase price of all purchases assets.

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- Definition

Represents the high end of the range, based on type of asset being financed, for the maximum amount of the obligation under the repurchase agreement that is guaranteed by the reporting entity, as a percent of the then currently outstanding repurchase price of all purchases assets.

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Represents the low end of the range, based on type of asset being financed, for the maximum amount of the obligation under the repurchase agreement that is guaranteed by the reporting entity, as a percent of the then currently outstanding repurchase price of all purchases assets.

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- Definition

Represents the number of extension options available to the entity to extend the term of the debt instrument.

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Represents the period by which the term of the debt instrument may be extended under each extension option.

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- Definition

Amount of loan asset expected to be sold under securitization during current fiscal period.

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- Definition

Aggregate amount of long-term debt as on the date of the most recent balance sheet.

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- Definition

Amount of long-term debt maturing within the first full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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- Definition

Amount of long-term debt maturing within the remainder of the fiscal year following the date of the most recent balance sheet presented in the financial statements.

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- Definition

Amount of long-term debt maturing within the remainder of the fiscal year and first full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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Amount of long-term debt maturing within the second full fiscal year following the date of the most recent balance sheet presented in the financial statements.

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- Definition

The percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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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.

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- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 15

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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The carrying amount as of the date of the latest financial statement presented of mortgage-related securities classified as available for sale or held for investment which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46(R)-8

-Paragraph B6

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)

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- Definition

Carrying value as of the balance sheet date , including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph 19, 20, 22

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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-Name Accounting Standards Codification

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Secured Financing Agreements (Details) (USD $)			9 Months Ended					9 Months Ended		3 Months Ended	9 Months Ended
Secured Financing Agreements (Details) (USD $)	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 Starwood Property Mortgage Sub-1, L.L.C. Wells Repurchase Agreement	Sep. 30, 2011 Starwood Property Mortgage Sub-2, L.L.C. Second Wells Repurchase Agreement option Y	Sep. 30, 2011 Starwood Property Mortgage Sub-3, L.L.C. Goldman Repurchase Agreement	Dec. 31, 2010 Starwood Property Mortgage Sub-3, L.L.C. Goldman Repurchase Agreement	Dec. 02, 2010 Starwood Property Mortgage Sub-3, L.L.C. Goldman Repurchase Agreement	Sep. 30, 2011 Starwood Property Mortgage, L.L.C. Wells RMBS Repurchase Agreement	Mar. 18, 2011 Starwood Property Mortgage, L.L.C. Wells RMBS Repurchase Agreement	Sep. 30, 2011 Starwood Property Mortgage, L.L.C. BAML Credit agreement	Sep. 30, 2011 Starwood Property Mortgage Sub-4, L.L.C. Deutsche Repurchase Agreement option Y	Sep. 30, 2011 SPT Rosslyn Holdings, L.L.C. Second Deutsche Repurchase Agreement	Sep. 30, 2011 SPT Real Estate Sub II, LLC BAML Credit agreement M	Sep. 30, 2011 SPT Real Estate Sub II, LLC BAML Credit agreement LIBOR	Sep. 30, 2011 SPT Real Estate Sub II, LLC BAML Credit agreement Base rate	Sep. 30, 2011 Second Wells Repurchase Agreement
Debt Instrument:
Loan portfolio collateralized			$ 390,800,000
Asset purchase capacity			109,500,000	350,000,000			150,000,000		100,000,000		150,000,000		120,300,000			350,000,000
Pricing rate, basis			one-month LIBOR	one-month LIBOR	one-month LIBOR			one-month LIBOR		LIBOR	one-month LIBOR	one-month LIBOR		LIBOR	base rate
Pricing margin (as a percent)			3.00%					1.50%
Additional pricing margin in event of default (as a percent)			4.00%	4.00%	2.00%			4.00%			4.00%	5.00%	2.00%
Debt Carry Value	604,335,000	579,659,000	109,500,000	238,000,000	92,200,000			38,900,000				5,300,000	120,300,000
Collateral Carry Value			163,400,000	415,800,000	121,200,000			132,400,000				162,100,000	174,700,000
Maximum liability guaranteed (as a percent)			25.00%			25.00%					25.00%
Maximum liability guaranteed											20,000,000
Pricing margin, low end of range (as a percent)				1.75%	1.95%						1.85%	3.50%		2.35%	1.35%
Pricing margin, high end of range (as a percent)				6.00%	2.25%						2.50%	5.00%		2.50%	1.50%
Number of extension options				2							2
Extended term (in years)				1							1
Maximum liability guaranteed, low end of range (as a percent)				25.00%
Maximum liability guaranteed, high end of range (as a percent)				100.00%
Amount of loan under credit agreement												117,400,000
Period of extension (in months)													12
Repayment of secured financings
2011 (reminder of)	2,158,000
2012	224,042,000
2013	378,135,000
Total	604,335,000
Secured financing maturities for the rest of 2011 and 2012			60,300,000	22,400,000									6,900,000
Loan expected to be sold under securitization during current fiscal period					$ 92,200,000			$ 38,900,000				$ 5,300,000