Represents the amount of equity grant forfeitures during the period.

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(ii)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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

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- Definition

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.

+ References

No definition available.

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Equity Compensation Plans - Unrecognized Compensation Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost at beginning of period	$ 20,269
Equity grants	15,817
Equity grant forfeitures	(557)
Equity compensation expense	(11,921)	$ (9,750)	$ (10,077)
Unrecognized Compensation Cost at End of Period	23,608	20,269
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation expense	(1,000)	(1,000)	(1,000)
Unrecognized Compensation Cost at End of Period	2,000
Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation expense	(7,000)	(6,000)	$ (6,000)
Unrecognized Compensation Cost at End of Period	14,000
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation expense	(3,000)
Unrecognized Compensation Cost at End of Period	7,000
Incentive Plans \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost at beginning of period	1,091
Equity grants	2,781
Equity grant forfeitures	(387)
Equity compensation expense	(1,092)
Unrecognized Compensation Cost at End of Period	2,393	1,091
Incentive Plans \| Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost at beginning of period	12,304
Equity grants	9,425
Equity grant forfeitures	(170)
Equity compensation expense	(7,167)
Unrecognized Compensation Cost at End of Period	14,392	12,304
Incentive Plans \| Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost at beginning of period	6,874
Equity grants	3,375
Equity compensation expense	(3,426)
Unrecognized Compensation Cost at End of Period	6,823	$ 6,874
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity grants	236
Equity compensation expense	(236)
Unrecognized Compensation Cost at End of Period	$ 0