Accrued Expenses (Schedule of Accrued Expenses) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accrued Expenses [Abstract]
Salaries and benefits	$ 7,669	$ 16,015
Real estate and property taxes	7,768	7,928
Unpaid capital expenditures	8,435	12,387
Other	29,662	27,335
Total accrued expenses	$ 53,534	$ 63,665