Sale of Energy Systems Division (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
Oct. 01, 2009	Dec. 31, 2012	Dec. 31, 2011
Divestiture, Cost of Significant Assets Sold, Sale Price	$ 10.0
Proceeds from Divestiture of Businesses	8.6
Divestiture, Contingent Consideration, Potential Consideration Receivable	1.4
Divestiture, Contingent Consideration, Potential Consideration Receivable, Cancelled		0.5
Gain (Loss) Related to Litigation Settlement		0.3	0.2
Contingent Upon Applied Utility Systems [Member]
Divestiture, Contingent Consideration, Potential Consideration Receivable	0.5
Retention of Certain Project And Contract Warranties And Other Obligation [Member]
Divestiture, Contingent Consideration, Potential Consideration Receivable	$ 0.9

Amount of potential cash receipts that could result from the contingent consideration arrangement.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of potential cash receipts that could result from the contingent consideration arrangement cancelled.

+ References

No definition available.

+ Details

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- Definition

The total consideration determined for the significant assets of a business division sold.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The net proceeds or assets obtained in excess of (less than) the net carrying amount of assets recorded, or assets distributed and liabilities assumed less than (in excess of) estimated litigation liability extinguished, in settlement of a litigation matter. Represents (for other than an insurance entity in its normal claims settlement process), the amount of income (expense) recognized in the period to settle pending or threatened litigation and insurance claims.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 9, 10, 11, 12

-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.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3179-108585

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15, 16

-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.

+ Details

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