Real Estate Investments and Related Intangibles - Nonmonetary Exchange Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($) property
Red Lobster [Member]
Real Estate [Line Items]
Number of real estate properties disposed in non monetary exchange \| property	15
Fair value of assets disposed	$ 50.1
Gain on acquisition and disposition of assets	$ 7.4
Bob Evans [Member]
Real Estate [Line Items]
Number of real estate properties acquired \| property	22
Fair value of properties acquired	$ 50.1

The fair value of assets acquired in noncash investing or financing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Name:	us-gaap_FairValueOfAssetsAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration