Debt Obligations Schedule of Maturities of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
2018	$ 8,142
2019	109,192
2020	182,323
2021	254,570
2022	341,169
Thereafter	922,390
Total	1,817,786	$ 1,060,690
Mortgages and notes payable
Debt Instrument [Line Items]
2018	8,142
2019	9,192
2020	7,323
2021	68,001
2022	31,169
Thereafter	122,390
Total	246,217	228,721
Revolving credit facility
Debt Instrument [Line Items]
2018	0
2019	0
2020	0
2021	61,569
2022	0
Thereafter	0
Total	61,569	176,969
Term loans
Debt Instrument [Line Items]
2018	0
2019	100,000
2020	175,000
2021	125,000
2022	310,000
Thereafter	430,000
Total	1,140,000	655,000
Secured loan facility due 2026
Debt Instrument [Line Items]
2018	0
2019	0
2020	0
2021	0
2022	0
Thereafter	175,000
Total	175,000	0
Secured loan facility due 2027
Debt Instrument [Line Items]
2018	0
2019	0
2020	0
2021	0
2022	0
Thereafter	195,000
Total	$ 195,000	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
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-Subparagraph (SX 210.5-02(22))
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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