Reversal of expenses associated with exit or disposal activities pursuant to an authorized plan.

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Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 5.P.3)
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-Publisher FASB
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
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Schedule of Restructuring Activities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 474	$ 458	$ 474	$ 458	$ 81	$ 281
Restructuring expenses	539	301	1,271	742
Payments for restructuring			(878)	(565)
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	539	301	1,271	742
UNITED STATES \| Operating Segments [Member] \| United States Electrical Construction And Facilities Services [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	0	0	0	0	0	255
Reversal of restructuring expenses				(106)
Restructuring expenses			0
Payments for restructuring			0	(149)
UNITED STATES \| Operating Segments [Member] \| United States Mechanical Construction And Facilities Services [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	293	0	293	0	0	26
Restructuring expenses			401	6
Payments for restructuring			(108)	(32)
UNITED STATES \| Operating Segments [Member] \| United States Building Services [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 181	$ 458	181	458	$ 81	$ 0
Restructuring expenses			870	842
Payments for restructuring			$ (770)	$ (384)