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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

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- Definition

The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.28,29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

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- Definition

Number of new stock issued during the period.

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- Definition

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

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Stockholders' Equity Stockholders' Equity (Details) - shares	3 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares		112,174
Stock Issued During Period, Shares, New Issues		3,439,636
Common Stock
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	0
Series E Preferred Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	0
Common Stock
Shares, Issued	261,844,521	261,844,521	255,114,603	250,749,665	250,139,408
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares		112,174	153,451	76,291
Stock Issued During Period, Shares, New Issues		6,339,636	3,410,433
Common Stock \| Series E Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues		7,480
Preferred Stock
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares		0
Preferred Stock \| Series F Preferred Stock [Member]
Shares, Issued	16,452,496	16,452,496	2,464,183	2,464,183	2,464,183
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		0	0	0
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares		0	0	0
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares		0	0
Preferred Stock \| Series E Preferred Stock [Member]
Shares, Issued	2,796,903	2,796,903	2,803,812	2,803,812	2,803,812
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		0	0	0
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership, Shares		0	0	0
Redemption of 6.75% Series G Cumulative Redeemable Shares, Shares		6,909	0
Home Acquisition [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	16,100,000
Home Acquisition [Member] \| Series F Preferred Stock [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	13,988,313	270,628	801,054	533,966