Supplemental Cash Flow and Other Information (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Significant Noncash Transactions [Line Items]
Accrual for capital expenditures	$ 2,000	$ 3,900	$ 1,200
Accrued liabilities	31,152	45,835
Accrued liabilities current [Member]
Other Significant Noncash Transactions [Line Items]
Accrued liabilities	31,200	45,800
Employee-related liabilities	$ 11,900	$ 15,100