Property and Equipment, Net - Depreciation Expense Table (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Depreciation Expense [Line Items]
Depreciation expense			$ 12,870	$ 13,050
Continuing Operations [Member]
Depreciation Expense [Line Items]
Depreciation expense	$ 6,540	$ 7,250	12,870	13,050
Cost of Sales [Member] | Continuing Operations [Member]
Depreciation Expense [Line Items]
Depreciation expense	6,030	6,740	11,840	11,940
Selling, General and Administrative Expenses [Member] | Continuing Operations [Member]
Depreciation Expense [Line Items]
Depreciation expense	$ 510	$ 510	$ 1,030	$ 1,110