Retirement Benefits - Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Jun. 30, 2012
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 183,372	$ 183,249
Accumulated benefit obligation	172,124	171,590
Fair value of plan assets	6,801	7,011
Obligations Exceed Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	183,372	176,942
Accumulated benefit obligation	172,124	165,283
Fair value of plan assets	6,801	0
Plan Assets Exceed Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	0	6,307
Accumulated benefit obligation	0	6,307
Fair value of plan assets	$ 0	$ 7,011

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If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=32704760&loc=d3e4179-114921

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2417-114920

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2417-114920

+ Details

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