Prepaid Expenses, Deferred Costs, And Other Assets - Components (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Prepaid Expenses, Deferred Costs, and Other Assets
Prepaid expense, Current	$ 44,480	$ 29,380
Interest rate swap contracts, Current	1,154
Deferred costs and other current assets, Current	50,472	37,727
Total, Current	96,106	67,107
Prepaid expenses, Noncurrent	34,264	17,049
Interest rate swap contracts	14,467	14,137
Deferred costs and other noncurrent assets	9,025	3,929
Total, Noncurrent	57,756	$ 35,115
Settlement receivables	$ 17,600