Fair Value of Financial Instruments - Estimated Incremental Borrowing Rates for Similar Types of Borrowing Arrangements (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Level 3 [Member] | Carrying Amount [Member] | Manufacturer Flooring Plans Payable with Interest Computed at 3.5% [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Manufacturer flooring plans payable with interest computed (Level 3)		$ 20,924
Level 3 [Member] | Carrying Amount [Member] | Manufacturer Flooring Plans Payable with Interest Computed at 5.0% [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Manufacturer flooring plans payable with interest computed (Level 3)	$ 21,507
Level 3 [Member] | Fair Value [Member] | Manufacturer Flooring Plans Payable with Interest Computed at 3.5% [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Manufacturer flooring plans payable with interest computed (Level 3)		19,533
Level 3 [Member] | Fair Value [Member] | Manufacturer Flooring Plans Payable with Interest Computed at 5.0% [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Manufacturer flooring plans payable with interest computed (Level 3)	18,579
Level 2 [Member] | Carrying Amount [Member] | Senior Unsecured Notes Due 2028 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Unsecured Notes Fair Value	1,240,688	1,239,967
Level 2 [Member] | Fair Value [Member] | Senior Unsecured Notes Due 2028 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Unsecured Notes Fair Value	$ 1,013,363	$ 1,242,850