Debt - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020
Line of Credit Facility [Line Items]
Revolving credit borrowing	$ 73,800,000	$ 73,800,000	$ 89,800,000	$ 96,800,000
Letters of credit outstanding	3,200,000	3,200,000
Other obligations	800,000	800,000
Financing lease obligations	3,600,000	3,600,000	$ 3,300,000	$ 3,700,000
Minimum [Member]
Line of Credit Facility [Line Items]
Fall of excess committed borrowing availability	15,000,000.0	15,000,000.0
Maximum [Member]
Line of Credit Facility [Line Items]
Fall of excess committed borrowing availability	$ 25,000,000.0	$ 25,000,000.0
Other Obligations [Member]
Line of Credit Facility [Line Items]
Debt instrument maturity year		2023
Debt instrument interest rate	6.11%	6.11%
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Amortization period on real estate component of borrowing base	15 years
Revolving credit borrowing	$ 73,800,000	$ 73,800,000
Weighted average interest rate	1.82%	1.82%
Excess committed borrowing availability	$ 167,200,000	$ 167,200,000
Unused commitment fees		0.25%
Fixed charge coverage ratio of credit facility	100.00%	100.00%
Revolving Credit Facility [Member] | Asset Backed Securities [Member]
Line of Credit Facility [Line Items]
Line of credit facility, expiration period	5 years
Line of credit facility, maximum borrowing capacity	$ 250,000,000.0	$ 250,000,000.0
Line of credit facility, maturity date	Sep. 29, 2026