Debt - Future Repayments of Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
Remaining 2016	$ 19,632
2017	47,826
2018	7,131
2019	25,204
2020	1,104,290
Thereafter	258,892
Total principal	1,462,975	$ 1,485,516
Unamortized debt premium/(discount)	1,060
Unamortized deferred loan costs	(11,615)
Total debt	$ 1,452,420	$ 1,473,427

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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.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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