Supplemental Cash Flow Information - Non-Cash Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Supplemental Cash Flow Information [Abstract]
Cash paid for interest	$ 180	$ 559	$ 1,542
Cash paid for income taxes	20,499	28,004	29,196
Non-cash transactions:
Change in accounts payable related to capital expenditures	(3,534)	(3,479)	3,787
Insurance premium financed by note payable	7,630	0	0
Distribution of net assets to MHI	$ 0	$ 0	$ 50,319