Intangible Assets (Future Amortization) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Future Amortization
2018	$ 2,519
2019	1,862
2020	1,271
2021	739
2022	499
Thereafter	7,695
Intangible assets, net	$ 14,585
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Amortizing intangibles, weighted-average remaining useful life	5 years
Future Amortization
2018	$ 2,291
2019	1,634
2020	1,043
2021	511
2022	271
Thereafter	180
Intangible assets, net	$ 5,930
Favorable Lease Rates
Finite-Lived Intangible Assets [Line Items]
Amortizing intangibles, weighted-average remaining useful life	38 years
Future Amortization
2018	$ 228
2019	228
2020	228
2021	228
2022	228
Thereafter	7,515
Intangible assets, net	$ 8,655

Finite-Lived Intangible Assets, Total Future Amortization Expense

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Finite-Lived Intangible Assets, Weighted Average Original Useful Lives

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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