Property, Plant and Equipment - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Assets held-for-sale, net book value	$ 4,100,000
Assets held-for-sale, recognized loss	$ 300,000
Impairment		$ 0	$ 0	$ 0