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

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-Topic 505
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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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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Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
	Apr. 02, 2020	Feb. 20, 2020	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares of beneficial interest, shares issued (in shares)			237,893,725			237,897,163
Common stock value			$ 2,379			$ 2,379
Distributions to shareholders		$ 35,684	$ 35,684	$ 92,714
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Distributions to common shareholders declared (in dollars per share)	$ 0.01
Distributions to shareholders	$ 2,379
Five Star
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares of beneficial interest, shares issued (in shares)					10,268,158
Five Star \| Shareholders
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares of beneficial interest, shares issued (in shares)					16,118,849
Common stock value					$ 59,801