Noncontrolling Interests - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Consolidated joint ventures and funds	$ 703,596	$ 685,888
Operating partnerships	904,683	$ 958,203
Redemption value	$ 886,487
Common units conversion basis	one-for-one

Describe the conversion features of common stock if such stock is convertible. That is, shares of common stock into which another convertible security was converted, or shares of common stock into which another class of common stock was converted.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

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 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

+ Details

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- Definition

Carrying amount of the equity interests owned by noncontrolling shareholders, partners, or other equity holders in joint ventures included in the entity's consolidated financial statements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4568740-111683

+ Details

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- Definition

Carrying amount of the equity interests owned by noncontrolling partners in an operating partnership included in the entity's consolidated financial statements.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Redemption value, as if currently redeemable, of redeemable noncontrolling interest classified as temporary equity and the election has been made to accrete changes in redemption value to the earliest redemption date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 24(b)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

+ Details

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