Acquisition of Millis Transfer (Details) - USD ($) $ in Thousands		12 Months Ended
	Aug. 26, 2019	Dec. 31, 2019
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs		$ 500
Business Combination, Total Consideration	$ 156,000
Noncash or Part Noncash Acquisition, Debt Assumed	93,300
Acquired Business Percent of Revenue		8.80%
Debt, Long-term and Short-term, Combined Amount		$ 0
Business Combination, Pro Forma Information, Net Income Change		3,000
Business Acquisition, Pro Forma Revenue		694,672
Business Acquisition, Pro Forma Net Income (Loss)		$ 75,951
Business Combination, Cash and Equity Transferred	$ 62,700