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

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The number of common stock per unit.

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The number of units outstanding as of the reporting date.

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

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

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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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Aggregate dividends declared during the period for each share of common stock outstanding.

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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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Fair value amount of debt instrument that was repurchased.

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

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The cash outflow to reacquire common stock during the period.

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Number of new stock issued during the period.

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Number of stock bought back by the entity at the exercise price or redemption price.

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Amount of stock repurchase plan authorized.

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Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Stockholders' Equity and Non-Controlling Interests (Details) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended		12 Months Ended
	Feb. 25, 2020 $ / shares	Mar. 31, 2020 USD ($) shares	Mar. 31, 2020 USD ($) item $ / shares shares	Mar. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares
Stockholders' Equity
Dividend declared (in dollars per share) \| $ / shares	$ 0.48		$ 0.48	$ 0.48
Shares issued under ATM Agreement \| shares			0	0
Authorized amount of share repurchases		$ 400,000	$ 400,000
Period for repurchase of common stock		1 year
Common stock repurchased (in shares) \| shares			1,925,421
Repurchase of common stock			$ 28,830
Debt repurchased amount		$ 0	0
Remaining capacity to repurchase common stock		$ 371,200	371,200
Net income attributable to non-controlling interests			$ 500	$ 6,125
Class A Units
Stockholders' Equity
Number of units outstanding \| shares		10,600,000	10,600,000
Value of shares issued to settle redemption			$ 400
CMBS JV
Stockholders' Equity
Non-controlling interest		$ 121,600	$ 121,600		$ 175,600
CMBS JV \| Joint Venture Partner
Stockholders' Equity
Equity Method Investment, Ownership Percentage		49.00%	49.00%
Woodstar II Portfolio \| Class A Units
Stockholders' Equity
Net income attributable to non-controlling interests			$ 5,100	$ 5,700
Woodstar II Portfolio \| Class A Units \| SPT Dolphin
Stockholders' Equity
Shares issued \| shares			1,800,000
Shares issued \| shares			10,200,000
Right to receive additional shares \| shares			1,900,000
Number of common stock per unit \| item			1
Woodstar II Portfolio \| Class A Units \| SPT Dolphin \| Non-Controlling Interests
Stockholders' Equity
Redemption of units \| shares			227,100,000		235,900,000
Woodstar II Portfolio \| CMBS JV \| Class A Units
Stockholders' Equity
Net income attributable to non-controlling interests			$ 6,000