Intangible Assets - Changes in Goodwill, Customer Relationships and Trademarks (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($)
Goodwill [Roll Forward]
Balance at beginning of period	$ 120,343
Additions	0
Balance at end of period	120,343
Finite-lived Intangible Assets [Roll Forward]
Balance at end of period	29,041
Customer Relationships— Acquired & Non-Compete Agreements
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	23,852
Additions	0
Amortization	(4,799)
Balance at end of period	19,053
Customer Relationships— Other
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	7,522
Additions	0
Amortization	(2,687)
Balance at end of period	4,835
Trademarks
Finite-lived Intangible Assets [Roll Forward]
Balance at beginning of period	5,708
Additions	0
Amortization	(555)
Balance at end of period	$ 5,153