Notes Payable, Long-Term Debt and Other Obligations (Schedule of Maturities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2019 Principal	$ 259,791
2019 Unamortized Discount	3,359
2019 Net	256,432
2020 Principal	244,478
2020 Unamortized Discount	29,465
2020 Net	215,013
2021 Principal	10,000
2021 Unamortized Discount	0
2021 Net	10,000
2022 Principal	10,000
2022 Unamortized Discount	0
2022 Net	10,000
2023 Principal	0
2023 Unamortized Discount	0
2023 Net	0
Thereafter Principal	1,175,000
Thereafter Unamortized Discount	0
Thereafter Net	1,175,000
Notes payable, long-term debt and other obligations	1,699,269
Unamortized Discount/ (Premium)	32,824
Total notes payable, long-term debt and other obligations	$ 1,666,445	$ 1,253,542