Related Party Transactions and Arrangements - Tax Protection Agreement (Details) - ARC [Member]	12 Months Ended
Dec. 31, 2016 property
Related Party Transaction [Line Items]
Indirect ownership interest in assets (percent)	100.00%
Number of properties owned	63
Number of vacant properties contributed	2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration