Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Description

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- Definition

Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting, Number Of Installments

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Options, Vesting Period

+ References

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- Definition

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(ii)

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

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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

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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 (i)

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

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 (a)(1)

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

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- Definition

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

+ 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)(iv)(1)

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option 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)(1)(i)

-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 per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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Share-Based Compensation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Capitalized share-based compensation cost			$ 0	$ 0
Number of stock options granted	0	12,511	0	106,466
Weighted-average exercise price for stock options granted		$ 35.46		$ 34.06
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation options awarded, vesting period			Stock options awarded to employees under the Company's 2008 Equity Compensation Plan ("2008 Plan") generally vest annually over a three-year period
Stock options term in years			10 years
Unrecognized compensation cost	2.1		2.1
Weighted-average period for which cost is expected to be recognized, in years			1 year 8 months 12 days
Weighted-average exercise price for outstanding stock options	$ 33.49		$ 33.49
Weighted-average remaining contractual term for outstanding stock options			5 years 7 months 6 days
Performance Award Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	0.8		0.8
Weighted-average period for which cost is expected to be recognized, in years			2 years 1 month 6 days
Share-based compensation awarded, number of installments			4
Board Dsus Granted To Nonemployee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	0.9		0.9
Board Dsus Granted To Nonemployee Directors \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period for which cost is expected to be recognized, in years			1 year
Service Award Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 7.6		$ 7.6
Weighted-average period for which cost is expected to be recognized, in years			3 years 2 months 12 days
Share-based compensation awarded, number of installments			4
One Executive
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation awarded, number of installments			12
Other Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation awarded, number of installments			16
Board DSUs And Dividend Equivalents Granted To Board
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation awarded, number of installments			3
Share-based compensation awarded, vesting period			3 years
Deferred Stock Unit Awards \| Former Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation awarded, vesting period			4 years