Goodwill - Carrying Value of Goodwill (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Goodwill [Roll Forward]
Balance, beginning of period				$ 56,660,000
Goodwill impairment recognized	$ 0		$ 0	(37,180,000)	$ 0
Balance, end of period	19,480,000			19,480,000
Energy Chemistry Technologies
Goodwill [Roll Forward]
Balance, beginning of period				37,180,000
Goodwill impairment recognized		$ (37,200,000)		(37,180,000)
Balance, end of period	0			0
Consumer and Industrial Chemistry Technologies
Goodwill [Roll Forward]
Balance, beginning of period				19,480,000
Goodwill impairment recognized	0			0
Balance, end of period	$ 19,480,000			$ 19,480,000