Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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-Name Regulation S-X (SX)

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- Definition

Convertible Debt Instrument, Conversion Ratio, Principal Amount, Basis

+ References

No definition available.

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- Definition

Amount of current revolving borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

No definition available.

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The item represents the amount by which the maximum borrowing capacity of a credit facility could be expanded if an attached accordion feature were exercised.

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No definition available.

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- Definition

Debt Instrument, Unused Borrowing Capacity, Fee, Basis Points

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No definition available.

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- Definition

This element represents the number of years a debt maturity may be optionally extended beyond the current maturity.

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No definition available.

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- Definition

This item represents the credit spread over the London Inter-Bank Offer Rate charged to the entity.

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No definition available.

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- Definition

This concept represents the outstanding balance of term loans.

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No definition available.

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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

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-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Paragraph 19, 20, 22

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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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-Topic 470

-SubTopic 20

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-Paragraph 4

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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-Topic 470

-SubTopic 20

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-Paragraph 5

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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-Paragraph 6

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(5))

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-Name Accounting Standards Codification

-Glossary Conversion Rate

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- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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-Name Accounting Standards Codification

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-SubTopic 30

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-Paragraph 2

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

+ References

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

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No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

Amount of the contractual principal due at the origination of the mortgage loan (face amount).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

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-Name Regulation S-X (SX)

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-Name Regulation S-X (SX)

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

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- Definition

The number of real estate properties owned as of the balance sheet date.

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No definition available.

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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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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.

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-Name Accounting Standards Codification

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-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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Debt (Narrative) (Details) (USD $)	9 Months Ended
Debt (Narrative) (Details) (USD $)	Sep. 30, 2014 properties	Sep. 30, 2013	Mar. 27, 2014	Dec. 31, 2013
Proceeds from convertible senior notes	$ 200,000,000	$ 0
Line of Credit Facility, Maximum Borrowing Capacity	700,000,000
Debt Instrument, Convertible, Conversion Ratio	13.926
Convertible Debt Instrument, Conversion Ratio, Principal Amount, Basis	1,000
Debt Instrument, Convertible, Conversion Price	$ 71.81
Debt Instrument, Convertible, Number of Equity Instruments	2,785,200
Convertible Debt	192,768,000		192,238,000	0
Debt Instrument, Convertible, Carrying Amount of Equity Component	7,762,000
Debt Instrument, Interest Rate, Effective Percentage	3.90%
Credit Facility, Current Revolving Borrowing Capacity	450,000,000
Credit Facility Expansion Amount	130,000,000
Debt Instrument, Unused Borrowing Capacity, Fee, Basis Points	40
Number of Real Estate Properties	163
Debt Instrument, Name, Convertible Senior Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	3.25%
Debt Issuance Cost	6,063,000
Debt Instrument, Name, Revolving Credit Facility [Member]
Debt Maturity, Extension Option, Number Of Years	1
Number of basis points over LIBOR	150
Unused balance of the unsecured revolving credit facility	369,000,000
Debt Instrument Name, Old Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity	620,000,000
Debt Instrument Name, $130m Term Loan - June 2020 Maturity [Member]
Term Loans, Outstanding Balance	130,000,000
Number of basis points over LIBOR	175
Debt Instrument Name, $120m Term Loans - June 2020 Maturity [Member]
Term Loans, Outstanding Balance	120,000,000
Number of basis points over LIBOR	175
Debt Instrument, Name, Fannie Mae (A) [Member]
Secured Debt	70,380,000
Debt Instrument, Interest Rate, Stated Percentage	6.85%
Debt Instrument, Name, Fannie Mae (B) [Member]
Secured Debt	7,162,000
Debt Instrument, Interest Rate, Stated Percentage	7.17%
Debt Instrument, Name, HUD Mortgages [Member]
Mortgage Loans on Real Estate, Face Amount of Mortgages	38,007,000
Secured Debt	37,973,000			0
Number of Real Estate Properties	9
Interest Rate Swap, Date Entered, March 2014 [Member]
Derivative, Fixed Interest Rate	3.91%
Derivative, Notional Amount	130,000,000
Interest Rate Swap, Date Entered, May 2012 [Member]
Derivative, Fixed Interest Rate	3.29%
Derivative, Notional Amount	40,000,000
Interest Rate Swap, Date Entered, June 2013 [Member]
Derivative, Fixed Interest Rate	3.86%
Derivative, Notional Amount	80,000,000
Allocated to Debt [Member] \| Debt Instrument, Name, Convertible Senior Notes [Member]
Debt Issuance Cost	5,788,000
Allocated to Equity [Member] \| Debt Instrument, Name, Convertible Senior Notes [Member]
Debt Issuance Cost	$ 275,000
Debt Instrument, Interest Rate, Period, Year 1 [Member] \| Debt Instrument, Name, HUD Mortgages [Member]
Mortgage Loans on Real Estate, Interest Rate	4.65%
Debt Instrument, Interest Rate, Period, After Year 1 [Member] \| Debt Instrument, Name, HUD Mortgages [Member]
Mortgage Loans on Real Estate, Interest Rate	4.30%