Fair Value of Assets and Liabilities (Details) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014 item property	Dec. 31, 2013
Assets and liabilities measured at fair value
Number of properties classified as held for sale	9
Cumulative impairments of properties held for sale	$ 22,545
Number of public issues of unsecured senior notes	6
Senior notes	1,742,893	1,093,337
Excess of fair value over aggregate book value	84,860
CommonWealth REIT (EQC)
Assets and liabilities measured at fair value
Investment in common shares	250,000
Five Star
Assets and liabilities measured at fair value
Investment in common shares	4,235,000
Recurring and Nonrecurring \| Total
Assets and liabilities measured at fair value
Assets held for sale	13,249
Investments in available for sale securities	27,797
Unsecured senior notes	1,827,753
Secured debt	735,341
Recurring and Nonrecurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets and liabilities measured at fair value
Investments in available for sale securities	27,797
Unsecured senior notes	1,827,753
Recurring and Nonrecurring \| Significant Other Observable Inputs (Level 2)
Assets and liabilities measured at fair value
Assets held for sale	13,249
Recurring and Nonrecurring \| Significant Unobservable Inputs (Level 3)
Assets and liabilities measured at fair value
Secured debt	$ 735,341

The cumulative amount of write-downs for impairments recognized during the period for long-lived assets held for sale.

No definition available.

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- Definition

Represents the number of public issues of unsecured senior notes.

+ References

No definition available.

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- Definition

The number of real estate properties owned by the entity, which are classified as held for sale as of the balance sheet date.

+ References

No definition available.

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- Definition

The amount by which the fair value of senior notes exceeds the book value.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Balance held at close of period in number of shares.

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- Definition

Fair value portion of notes payable.

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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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