Summarized Quarterly Results of Operations (Parenthetical) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Line Items]
U.S. tax benefit as a result of a worthless stock deduction		$ 3,037	$ 4,864	$ 7,395
Loss on extinguishment of debt	$ 1,900	$ 0	$ (1,888)	$ 0
Tax cuts and jobs act of 2017 net benefit to income tax expense	1,200
Brazil Business [Member]
Quarterly Financial Information Disclosure [Line Items]
Loss on sale of business	35,000
U.S. tax benefit as a result of a worthless stock deduction	$ 15,000