Leases (Details 2) $ in Thousands	Dec. 31, 2017 USD ($)
As Lessor - Operating Leases
2018	$ 1,139,552
2019	892,754
2020	649,096
2021	433,319
2022	258,381
Thereafter	210,213
Total	3,583,315
As Lessor - Direct Financing and Sales-Type Leases
2018	110,692
2019	95,759
2020	99,470
2021	68,349
2022	54,603
Thereafter	68,230
Total	497,103
As Lessee - Operating Leases
2018	84,824
2019	63,435
2020	41,034
2021	24,948
2022	18,495
Thereafter	38,288
Total	$ 271,024

Amount of minimum lease payments to be received by the lessor for capital leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)
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Amount of minimum lease payments to be received by the lessor for capital leases in the next 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 minimum lease payments to be received by the lessor for capital leases 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 required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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