Segment Reporting - Narratives (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)
Segment Reporting Information
Number of reportable segments \| segment	2
Straight line rent adjustment	$ 2,800	$ 3,500
Revenues	113,282	123,005
Operating Segments \| Net Lease
Segment Reporting Information
Bad debt expense	4,400	1,600
Revenues	96,992	112,523
All Other
Segment Reporting Information
Revenues	7,245	1,740
All Other \| ASU 2017-05
Segment Reporting Information
Revenues	2,200
CMBS \| Level 3 \| Nonrecurring
Segment Reporting Information
Impairment on equity method investment	$ 5,400
Agrokor \| Real estate \| Level 3 \| Nonrecurring
Segment Reporting Information
Impairment on equity method investment		4,500
KBR \| Assets held for sale
Segment Reporting Information
Accelerated amortization of intangible liabilities		$ 3,300

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84176398&loc=d3e2921-110230

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of the adjustment to rental revenues to measure escalating leasing revenues on a straight line basis.

+ References

No definition available.

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