Represents the number of mortgage loans collateralized by a MOB property.

No definition available.

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- Definition

Represents the number of mortgage loans closed.

+ References

No definition available.

+ Details

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- Definition

The number of real estate properties serving as collateral for debt as of the balance sheet date.

+ References

No definition available.

+ Details

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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 and amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

No definition available.

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)

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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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.

+ References

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

-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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Interest rate stated in the contractual debt agreement.

+ References

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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-Publisher FASB

-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

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- Definition

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of long-term debt maturities after year five following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-Subparagraph b

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-Topic 470

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Amount of long-term debt maturing within the next twelve months following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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Amount of long-term debt maturing in year five following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

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Amount of long-term debt maturing in year four following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

+ References

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Amount of long-term debt maturing in year three following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed of determinable prices and dates.

+ References

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Amount of long-term debt maturing in year two following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

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Represents a total which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(d))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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The net book value of real estate property held for investment purposes.

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Indebtedness (Details 2) (USD $) In Thousands, unless otherwise specified																																						1 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Unsecured Debt	Dec. 31, 2010 Unsecured Debt	Dec. 31, 2011 Senior unsecured notes 8.625%	Dec. 31, 2010 Senior unsecured notes 8.625%	Dec. 31, 2011 Senior unsecured notes 4.30%	Jan. 31, 2011 Senior unsecured notes 4.30%	Dec. 31, 2011 Senior unsecured notes 6.75%	Dec. 31, 2010 Senior unsecured notes 6.75%	Apr. 30, 2010 Senior unsecured notes 6.75%	Dec. 31, 2011 Unsecured senior notes due 2021	Dec. 31, 2011 Secured and Other Debt	Dec. 31, 2010 Secured and Other Debt	Dec. 31, 2011 Mortgage 6.03% maturing in March 2012 Property	Dec. 31, 2011 Mortgage 6.73% maturing in June 2012 Property	Dec. 31, 2010 Mortgage 6.73% maturing in June 2012	Dec. 31, 2011 Mortgages 6.97% maturing in July 2012 Property	Dec. 31, 2010 Mortgages 6.97% maturing in July 2012	Dec. 31, 2011 Mortgage 6.07% maturing in September 2012 Property	Dec. 31, 2011 Mortgage 6.50% maturing in Jan 2013 Property	Dec. 31, 2010 Mortgage 6.50% maturing in Jan 2013	Dec. 31, 2011 Mortgages 6.11% maturing in Dec 2013 Property	Dec. 31, 2010 Mortgages 6.11% maturing in Dec 2013	Dec. 31, 2011 Mortgage 6.91% maturing in Dec 2013 Property	Dec. 31, 2010 Mortgage 6.91% maturing in Dec 2013	Dec. 31, 2011 Mortgage 5.83% maturing in June 2014 Property	Dec. 31, 2011 Mortgage 5.65% maturing in June 2015	Dec. 31, 2011 Mortgage 6.37% maturing in July 2015 Property	Dec. 31, 2011 Mortgage 5.66% maturing in July 2015 Property	Dec. 31, 2011 Mortgage 5.88% maturing in July 2015 Property	Dec. 31, 2011 Mortgage 5.81% maturing in October 2015 Property	Dec. 31, 2011 Mortgage 5.97% maturing in April 2016 Property	Dec. 31, 2011 Mortgage 5.924% maturing in November 2016 Property	Dec. 31, 2011 Mortgage 6.25% maturing in November 2016 Property	Dec. 31, 2011 Mortgages 6.54% maturing in May 2017 Property	Dec. 31, 2010 Mortgages 6.54% maturing in May 2017	Aug. 31, 2009 Mortgages 6.71% and 6.39% maturing in Sept 2019 Mortgage	Dec. 31, 2011 Mortgages 6.71% and 6.39% maturing in Sept 2019	Dec. 31, 2011 Mortgage 6.71% maturing in Sept 2019 Property	Dec. 31, 2010 Mortgage 6.71% maturing in Sept 2019	Dec. 31, 2011 Mortgage 6.39% maturing in Sept 2019	Dec. 31, 2010 Mortgage 6.39% maturing in Sept 2019	Dec. 31, 2011 Mortgage 7.31% and 7.85% maturing in Jan 2022 Mortgage	Dec. 31, 2011 Mortgage 7.31% maturing in Jan 2022 Property	Dec. 31, 2010 Mortgage 7.31% maturing in Jan 2022	Dec. 31, 2011 Mortgage 7.85% maturing in Jan 2022	Dec. 31, 2010 Mortgage 7.85% maturing in Jan 2022	Dec. 31, 2011 Mortgage 6.25% maturing in January 2033 Property	Dec. 31, 2011 Mortgage 5.95% maturing in September 2038 Property	Dec. 31, 2011 Mortgage bonds Property	Dec. 31, 2010 Mortgage bonds	Dec. 31, 2011 Capital leases Property	Dec. 31, 2010 Capital leases	Dec. 31, 2011 Mortgage 6.07% maturing in Sept 2012 and 5.65% maturing in June 2015 Mortgage
Indebtedness
Face Amount			$ 975,000	$ 425,000	$ 225,000	$ 225,000	$ 250,000		$ 300,000		$ 200,000	$ 300,000
Unamortized Discount			9,230	2,120		128	2,154		1,777	1,992		5,299
Total secured	861,615	654,010											861,424	653,590	12,400	2,356	2,419	30,580	31,552	3,177	4,224	4,307	10,920	11,255	14,009	14,245	37,619	5,215	11,747	13,310	2,946	4,684	6,581	93,133	12,695	47,688	48,565			300,669	303,948	200,078	202,449		3,515	3,742	1,725	1,833	3,619	9,623	14,700	14,700	14,200	14,575
Interest rate (as a percent)					8.625%	8.625%	4.30%	4.30%	6.75%		6.75%	6.75%			6.03%	6.73%	6.73%	6.97%	6.97%	6.07%	6.50%	6.50%	6.11%	6.11%	6.91%	6.91%	5.83%	5.65%	6.37%	5.66%	5.88%	5.81%	5.97%	5.924%	6.25%	6.54%	6.54%			6.71%	6.71%	6.39%	6.39%		7.31%	7.31%	7.85%	7.85%	6.25%	5.95%	5.875%	5.875%	7.70%	7.70%
Number of Properties as Collateral															1	1		16		1	1		4		2		2		1	3	1	1	1	2	1	8				28					1				1	2	1		2
Initial Cost of Collateral	4,721,591	3,761,712											1,287,165		17,158	4,450		70,114		22,143	7,560		17,034		36,359		79,000		14,849	26,606	15,397	8,600	10,272	157,500	22,102	62,500				617,161					18,827				5,200	11,425	34,307		28,601
Net Book Value of Collateral	4,091,330	3,222,840											1,142,035	754,069	17,076	3,696	3,780	61,542	63,300	21,838	7,406	7,450	14,814	15,225	33,702	34,347	79,108		14,697	26,377	15,173	8,532	10,194	157,640	21,984	57,873	59,067			505,214	506,805				17,243	17,703			4,807	19,589	27,503	28,409	16,027	17,983
Unamortized net premiums	191	420
Number of mortgages closed																																						2
Number of mortgages																																												2											2
Effective interest rate (as a percent)																																							6.39%
Net book value of the assets encumbered by capital leases																																																					14,211	14,575
Required principal payments on outstanding debt
2012	286,119
2013	41,316
2014	49,161
2015	48,967
2016	360,587
Thereafter	$ 1,050,274