Outstanding and Exercisable Stock Options by Exercise Price (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End	3,877
Weighted-Average Remaining Contractual Life	7 months 6 days
Weighted-Average Exercise Price	$ 45.00
Under $10.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End	5
Weighted-Average Remaining Contractual Life	1 year 6 months
Weighted-Average Exercise Price	$ 9.65
$10.01-$20.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End	590
Weighted-Average Remaining Contractual Life	2 years 1 month 6 days
Weighted-Average Exercise Price	$ 12.86
$20.01-$30.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End	33
Weighted-Average Remaining Contractual Life	2 months 12 days
Weighted-Average Exercise Price	$ 23.38
$30.01-$40.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End	136
Weighted-Average Remaining Contractual Life	1 year 3 months 18 days
Weighted-Average Exercise Price	$ 36.31
Over $40.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End	3,113
Weighted-Average Remaining Contractual Life	3 months
Weighted-Average Exercise Price	$ 51.77

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

+ Details

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a, b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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