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

+ References

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
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-Section 50
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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The cash outflow from the acquisition of real estate intended to generate income for the owner; excludes land acquired for use by the owner.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
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The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

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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.

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No definition available.

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Real Estate (Acquisitions) (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
Real Estate (Acquisitions) (Details) $ in Thousands	Apr. 30, 2017 lease property	Sep. 30, 2017 USD ($) lease	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) lease_asset property	Dec. 31, 2015 USD ($)
Real Estate Properties [Line Items]
Number of net lease assets \| lease_asset				1
Acquisitions of real estate assets			$ 6,600	$ 38,433	$ 0
Payments for land and funded tenant improvements				$ 3,900
Number of properties acquired \| property				2
Net Lease Asset
Real Estate Properties [Line Items]
Acquisitions of real estate assets			$ 6,600	$ 32,700
Fair value in excess of carrying value		$ 1,500
Operating leases, term				99 years
Real Estate Acquired in Satisfaction of Debt
Real Estate Properties [Line Items]
Fair value of assets acquired				$ 13,400
Ground Net Lease Business \| Safety, Income and Growth, Inc.
Real Estate Properties [Line Items]
Number of net lease assets \| lease	7
Number of properties acquired \| property	12
Master Lease
Real Estate Properties [Line Items]
Number of leases modified \| lease		2