Uncertain Tax Positions (Long-Term Liability For Unrecognized Tax Benefits, Excluding Interest And Penalties) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Uncertainties [Abstract]
Deferred income taxes (contra assets)	$ 0bid_DeferredIncomeTaxesContraAssets	$ 0bid_DeferredIncomeTaxesContraAssets	$ 12,445bid_DeferredIncomeTaxesContraAssets
Accrued income taxes (current)	0	0	482
Accrued income taxes (long-term)	22,798	25,423	22,473
Total liability for unrecognized tax benefits	$ 22,798us-gaap_UnrecognizedTaxBenefits	$ 25,423us-gaap_UnrecognizedTaxBenefits	$ 35,400us-gaap_UnrecognizedTaxBenefits	$ 34,689us-gaap_UnrecognizedTaxBenefits

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns recorded within current accrued income tax assets (liabilities) as of the balance sheet date.

No definition available.

+ Details

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns recorded within accrued non-current income tax assets (liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns recorded within deferred income tax assets (liabilities) as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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