Related Party Transactions (Details) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011
Related Party Transactions
Auction commission revenues	$ 1,800,000	$ 5,000,000
Net accounts receivable from related party transaction	13,000,000	13,000,000
Net accounts receivable	$ 1,000,000,000	$ 1,000,000,000
Percentage of revenue from related party to total revenue		1.00%
Percentage of net account receivable from related party to total account receivable		1.00%

Auction Commission Revenues From Related Party

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- Definition

Percentage Of Account Receivable From Related Party To Total Account Receivable

+ Details

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- Definition

Percentage of Revenue From Related Party To Total Revenue

+ Details

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- Definition

Related Party Transactions [Abstract]

+ Details

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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 4
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 3
-Subparagraph a
-Article 5

+ Details

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- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph k
-Subparagraph 1
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 57
-Paragraph 2
-Subparagraph d

+ Details

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