Outstanding and Exercisable Stock Options by Exercise Price (Detail) shares in Thousands	12 Months Ended
Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End \| shares	119
Weighted-Average Remaining Contractual Life	9 months 18 days
Weighted-Average Exercise Price \| $ / shares	$ 14.97
Under $10.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End \| shares	1
Weighted-Average Remaining Contractual Life	3 years
Weighted-Average Exercise Price \| $ / shares	$ 8.59
$10.01-$20.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End \| shares	112
Weighted-Average Remaining Contractual Life	9 months 18 days
Weighted-Average Exercise Price \| $ / shares	$ 13.89
$20.01-$30.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End \| shares	1
Weighted-Average Remaining Contractual Life	2 years
Weighted-Average Exercise Price \| $ / shares	$ 24.41
Over $40.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options at Year End \| shares	5
Weighted-Average Remaining Contractual Life	1 year
Weighted-Average Exercise Price \| $ / shares	$ 40.98

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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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

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

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

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