Business Combinations - Estimates of Acquired Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 18,200	$ 2,611
Weighted Average Estimated Useful Life (in years)	12 years	8 years
Trademarks and tradenames
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 4,400	$ 1,145
Weighted Average Estimated Useful Life (in years)	15 years	15 years
Covenants not-to-compete
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 2,600	$ 227
Weighted Average Estimated Useful Life (in years)	5 years	5 years
Backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 0	$ 529
Weighted Average Estimated Useful Life (in years)	0 years	2 years