Credit Facilities and Long term Debt (Details) $ in Millions	Aug. 30, 2021 CAD ($) lineOfCredit	Aug. 01, 2021 USD ($)	Sep. 30, 2021
Line of Credit
Short-term Debt [Line Items]
Debt instrument, number | lineOfCredit	3
Line of Credit | Revolving Credit Facility
Short-term Debt [Line Items]
Credit facility borrowing capacity (up to)	$ 50
Line of Credit | Floor Plan Financing for New and Used Vehicles
Short-term Debt [Line Items]
Credit facility borrowing capacity (up to)	300
Line of Credit | Wholesale Lease Financing
Short-term Debt [Line Items]
Credit facility borrowing capacity (up to)	$ 350
Senior Notes | 5.250% Senior notes due 2025
Short-term Debt [Line Items]
Aggregate principal amount		$ 300,000,000
Stated interest rate (percent)		5.25%	5.25%
Debt redemption price, percentage of principal amount redeemed		102.625%
Minimum | Line of Credit
Short-term Debt [Line Items]
Basis spread on variable rate	0.25%
Maximum | Line of Credit
Short-term Debt [Line Items]
Basis spread on variable rate	1.50%