Number of shares of equity interests issuable upon contingent consideration in business acquisition.

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The number of units outstanding as of the reporting date.

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- Definition

Number of shares issued during the period through an agent under an "at the market" equity offering program agreement.

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No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Carrying amount of the equity interests owned by noncontrolling shareholders, partners, or other equity holders in joint ventures included in the entity's consolidated financial statements.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

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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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No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

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Stockholders' Equity and Non-Controlling Interests - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2018	May 31, 2017
Equity Incentive Plans
Shares issued ATM (in shares)			0	0
Net income attributable to non-controlling interests	$ 11,885	$ 12,900	$ 33,107	$ 26,705
CMBS JV
Equity Incentive Plans
Non-controlling interest	$ 129,600		$ 129,600		$ 126,700
CMBS JV \| Joint Venture Partner
Equity Incentive Plans
Ownership percentage	49.00%		49.00%
CMBS JV
Equity Incentive Plans
Ownership percentage	51.00%		51.00%
Class A Units
Equity Incentive Plans
Value of shares issued to settle redemption			$ 900
Number of units outstanding (in shares)	9,800,000		9,800,000
Woodstar II Portfolio \| Class A Units
Equity Incentive Plans
Net income attributable to non-controlling interests	$ 4,700	5,100	$ 14,700	15,300
Woodstar II Portfolio \| Class A Units \| CMBS JV
Equity Incentive Plans
Net income attributable to non-controlling interests	$ 6,700	$ 6,800	$ 16,700	$ 7,600
Subsidiaries \| Woodstar II Portfolio \| Class A Units
Equity Incentive Plans
Shares issued (in shares)						10,200,000
Right to receive additional shares (in shares)			1,900,000			1,900,000
Subsidiaries \| Woodstar II Portfolio \| Class A Units \| Non- Controlling Interests
Equity Incentive Plans
Redemption of units			$ 208,500		$ 226,700
Starwood Property Trust, Inc. Equity Plan and Manager Equity Plan
Equity Incentive Plans
Number of shares of authorized for issuance (in shares)							11,000,000
Number of shares available for future grants (in shares)	3,100,000		3,100,000