Schedule of Share-based Compensation, Stock Options, Activity (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Shares [Abstract]
Outstanding at January 1	11,859	15,504	20,564
Granted			1
Exercised	(96)	(58)	(11)
Forfeited or expired	(4,179)	(3,587)	(5,050)
Outstanding at December 31	7,584	11,859	15,504
Exercisable at December 31	7,584	11,859	15,504
Weighted-Average Grant Price [Abstract]
Outstanding at January 1	$ 52.01	$ 49.29	$ 48.97
Granted			$ 8.59
Exercised	$ 9.25	$ 8.76	$ 8.33
Forfeited or expired	$ 49.61	$ 40.54	$ 48.06
Outstanding at December 31	$ 53.88	$ 52.01	$ 49.29
Exercisable at December 31	$ 53.88	$ 52.01	$ 49.29

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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The weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncompliance with plan terms during the reporting period.

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Net number of share options (or share units) granted during the period.

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The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of share options (or share units) exercised during the current period.

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