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Share Based Compensation Arrangement by Share Based Payment Award, Options, Contractual Term

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Vested in Period

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Options, Vested in Period, Total Fair Value

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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 50

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph i

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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-Publisher FASB

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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph h

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Stock-Based Compensation - Additional Information (Detail) (JPY ¥) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 Year	May 01, 2011	Dec. 31, 2010	May 01, 2010	Dec. 31, 2009	May 01, 2009	Dec. 31, 2008	May 01, 2008
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Number of common stock shares authorized to be acquired under stock options granted		912,000		890,000		954,000		592,000
Vesting period
Contractual term (in years)	4
Grant-date fair value per share of stock options	¥ 772		¥ 988		¥ 699		¥ 1,247
Recognized compensation cost for stock options	¥ 748		¥ 643		¥ 564
Total unrecognized compensation cost related to nonvested stock options	606
Weighted-average period over which unrecognized compensation cost related to nonvested stock options is expected to be recognized (in years)	0.84
Fair value of vested shares	547		696
Cash received from the exercise of stock options	¥ 216