Segment Reporting (Schedule Of Revenue And (Loss) Income Before Taxes by Segment) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Segment Reporting [Line Items]
Revenues	$ 58,210,000	$ 73,060,000	$ 547,587,000	$ 456,349,000
Segment (loss) income before taxes	(57,900,000)	(38,482,000)	123,539,000	85,668,000
Auction [Member]
Segment Reporting [Line Items]
Revenues	52,916,000	55,104,000	516,841,000	420,532,000
Segment (loss) income before taxes	(51,399,000)	(42,034,000)	120,424,000	76,410,000
Finance [Member]
Segment Reporting [Line Items]
Revenues	3,507,000	3,499,000	12,193,000	12,240,000
Segment (loss) income before taxes	752,000	4,365,000	9,075,000	10,374,000
Non-operating gain related to the remeasurement of a foreign currency	1,700,000	2,000,000	800,000	2,000,000
Dealer [Member]
Segment Reporting [Line Items]
Revenues	591,000	14,991,000	16,848,000	25,848,000
Segment (loss) income before taxes	(7,006,000)	(1,236,000)	(7,979,000)	(2,561,000)
Inventory writedowns	5,700,000		8,300,000
All Other [Member]
Segment Reporting [Line Items]
Revenues	1,780,000	1,033,000	4,876,000	3,401,000
Segment (loss) income before taxes	1,238,000	693,000	3,601,000	2,089,000
Reconciling Items [Member]
Segment Reporting [Line Items]
Revenues	(584,000)	(1,567,000)	(3,171,000)	(5,672,000)
Segment (loss) income before taxes	$ (1,485,000)	$ (270,000)	$ (1,582,000)	$ (644,000)