Defined Benefit Pension Plan's Weighted Average Asset Allocation and Weighted Average Target Allocation (Detail)	12 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Weighted Average Asset Allocation
Equity securities	54.00%	55.00%
Debt securities	40.00%	40.00%
Commodities
Cash and money market funds	6.00%	5.00%
Defined Benefit Plan, Actual Plan Asset Allocations, Total	100.00%	100.00%
Target Allocation
Equity securities	46.00%
Debt securities	49.00%
Commodities	2.00%
Cash and money market funds	3.00%
Defined Benefit Plan Target Allocation Percentage, Total	100.00%

Defined Benefit Plan, Commodities

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Defined Benefit Plan Target Allocation Percentage Of Commodities

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Defined Benefit Plan Target Allocation Percentage, Total

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The percentage of the fair value of debt securities to the fair value of total plan assets held as of the measurement date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Publisher FASB

-Name Accounting Standards Codification

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The percentage of the fair value of equity securities to the fair value of total plan assets held as of the measurement date.

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The percentage of the fair value of investments other than debt securities, equity securities, and real estate to the fair value of total plan assets held as of the measurement date.

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Target allocation percentage of investments in debt securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 715

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Target allocation percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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Target allocation percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

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The aggregate percentage of the fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of total plan assets held as of the measurement date.

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