Goodwill and Intangible Assets - Classes of Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Total cost of intangibles	$ 156,818	$ 156,424
Accumulated Amortization	33,465	29,784
Finite-lived intangibles, net	109,906
Intangible assets, net	123,353	126,640
Trade Name - Indefinite-lived
Finite-Lived Intangible Assets [Line Items]
Trade Name - Indefinite-lived	13,447	13,447
Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Cost	143,371	139,271
Accumulated Amortization	33,465	26,078
Finite-lived intangibles, net	$ 109,906	113,193
Trade Name - Indefinite-lived
Finite-Lived Intangible Assets [Line Items]
Cost		3,679
Accumulated Amortization		3,679
Finite-lived intangibles, net		$ 0
Non-Compete Agreement
Finite-Lived Intangible Assets [Line Items]
Amortization Period		24 months
Cost		$ 27
Accumulated Amortization		27
Finite-lived intangibles, net		$ 0
Minimum | Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Amortization Period	84 months
Minimum | Trade Name - Indefinite-lived
Finite-Lived Intangible Assets [Line Items]
Amortization Period		12 months
Maximum | Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Amortization Period	180 months	180 months
Maximum | Trade Name - Indefinite-lived
Finite-Lived Intangible Assets [Line Items]
Amortization Period		24 months