Financial Statement Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended				9 Months Ended
	Mar. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Inventory [Line Items]
Inventories		$ 2,245,846				$ 2,245,846		$ 2,772,777
Accounts Receivable, Allowance for Credit Loss, Current		68,000				68,000		53,000
Accounts Receivable, Credit Loss Expense (Reversal)						23,000	$ 10,000
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts Receivable, Credit Loss Expense (Reversal)						23,000	10,000
Adoption of ASU 2016-13 (see Note 3)				$ (3,000)		(2,519)
Accounts Receivable, Allowance for Credit Loss, Current		68,000				68,000		53,000
Decrease in Market Capitalization	40.00%
Amount that fair value exceeds carrying value	12.00%			12.00%
Rent Reductions in Selling, General and Administrative Expenses		1,000	$ 2,000
Payments for Repurchase of Common Stock					$ 101,000	88,006	$ 291,813
AftermarketAndRefurbishedProducts [Member]
Inventory [Line Items]
Inventories		1,862,044				1,862,044		2,297,895
SalvageAndRemanufacturedProducts [Member]
Inventory [Line Items]
Inventories		364,082				364,082		447,908
ManufacturedProducts [Member]
Inventory [Line Items]
Inventories		19,720				19,720		26,974
Inventory, Raw Materials and Supplies, Gross		15,000				15,000		17,000
Inventory, Work in Process, Gross		3,000				3,000		3,000
Inventory, Finished Goods, Gross		$ 1,000				$ 1,000		$ 6,000
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lessee Lease Renewal Term						1 year
Lessee Lease Renewal Term						1 year
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lessee Lease Renewal Term						40 years
Lessee Lease Renewal Term						40 years
Accounting Standards Update 2016-13 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of ASU 2016-13 (see Note 3)				$ 3,000