Dispositions and Real Estate Assets Held for Sale - Restricted Cash Related to Dispositions (Details) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
Discontinued Operations and Disposal Groups [Abstract]
Payments of debt extinguishment costs	$ 48.4

The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

No definition available.

Name:	us-gaap_PaymentsOfDebtExtinguishmentCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration