Variable Interest Entities (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Consolidated VIEs
Variable Interest Entity
Total assets and liabilities of our consolidated VIEs, excluding the Operating Partnership	$ 3,638,483,000	$ 1,762,322,000
Unconsolidated VIEs
Variable Interest Entity
Net carrying amount of our investments in nonconsolidated VIEs	$ 392,150,000	$ 414,003,000

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5728-111685

Name:	us-gaap_VariableInterestEntityNonconsolidatedCarryingAmountAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant