Debt Obligations, net - Future Scheduled Maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Maturities of Long-term Debt [Abstract]
2019 (remaining six months)	$ 0
2020	400,000
2021	435,511
2022	1,110,938
2023	643,500
Thereafter	522,444
Total principal maturities	3,112,393	$ 3,661,617
Unamortized discounts and deferred financing costs, net	(43,837)	(52,531)
Total debt obligations, net	3,068,556	3,609,086
Unsecured Debt
Maturities of Long-term Debt [Abstract]
2019 (remaining six months)	0
2020	400,000
2021	275,000
2022	1,062,500
2023	0
Thereafter	100,000
Total principal maturities	1,837,500
Unamortized discounts and deferred financing costs, net	(35,026)
Total debt obligations, net	1,802,474
Secured Debt
Maturities of Long-term Debt [Abstract]
2019 (remaining six months)	0
2020	0
2021	160,511
2022	48,438
2023	643,500
Thereafter	422,444
Total principal maturities	1,274,893	$ 1,449,117
Unamortized discounts and deferred financing costs, net	(8,811)
Total debt obligations, net	$ 1,266,082

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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-Publisher FASB
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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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