The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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)(iv)(3)

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

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Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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)(2)(iii)(1)

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

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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Stockholders' Equity - Activities Under Equity Plan (Detail)	3 Months Ended												39 Months Ended	31 Months Ended	12 Months Ended	0 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2014	Jul. 08, 2014	May 16, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning Balance, Equity securities available																	2,194,986
Granted, shares	(7,110)	(6,006)	(5,093)	(6,475)	(6,266)	(4,606)	(4,712)	(5,350)	(5,263)	(4,084)	(3,769)	(3,785)	(62,519)
Ending Balance, Equity securities available													1,747,586	1,747,586	1,747,586		2,194,986
Short-Term Incentive Plan (STIP) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares														(41,702)
Restricted Stock Units [Member] \| 2011 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited, shares														209,382	57,338
Granted, shares														(557,484)	0
Common Stock [Member] \| Two Thousand Four Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares														(5,820)		(5,820)
Non Executive Directors [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited, shares														3,189
Granted, shares														(54,965)