Uncompleted Contracts - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Jun. 30, 2013
Customer Contracts [Line Items]
Billings in accounts receivable to be collected within one year	$ 23.7	$ 19.9
Contract Receivable Retainage, Due in Next Twelve Months	3.6	3.1
S.M. Electric Company
Customer Contracts [Line Items]
Estimate of the remaining amount to be collected	0.7
Contract Receivable	$ 2.9

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Amount billed to customers under long-term contracts or programs but not paid. Excludes amounts due that have been withheld because of retainage provisions in a contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 910

-SubTopic 310

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6471494&loc=d3e49354-109356

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3(c))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c

-Article 5

+ Details

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract to be collected in the remainder of the fiscal year following the latest fiscal year ended.

+ References

No definition available.

+ Details

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract to be collected in the next fiscal year following the latest fiscal year.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c

-Article 5

+ Details

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- Definition

Amount of billed or unbilled claims or other similar items subject to uncertainty concerning their determination or ultimate realization under long-term contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3(c)(3))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c(3)

-Article 5

+ Details

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