Acquisitions and Dispositions - Subsequent Acquisition - Additional Information (Details) - LKQD [Member] - USD ($)		12 Months Ended
	Jan. 16, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Acquisition related costs		$ 300,000
Subsequent Event [Member]
Business Acquisition [Line Items]
Acquisition date	Jan. 16, 2018
Cash paid in business acquisition	$ 90,000,000
Maximum Earnout payment	35,000,000
Subsequent Event [Member] | Revolving loans [Member]
Business Acquisition [Line Items]
Portion of business acquisition consideration funded by revolving credit	$ 44,000,000