Goodwill Allocated, Percentage

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- Definition

Goodwill and Intangible Assets [Line Items]

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- Definition

Goodwill Impairment Testing, Perpetual Growth Rate, Percentage

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- Definition

Goodwill Impairment Testing, Weighted Average Cost of Capital, Percentage

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

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Goodwill and Identifiable Intangible Assets - Narrative (Details) - USD ($)		3 Months Ended								12 Months Ended
	Oct. 01, 2016	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets[Line Items]
Goodwill		$ 979,628,000				$ 843,170,000				$ 979,628,000	$ 843,170,000	$ 834,102,000
Goodwill acquired										135,900,000	9,600,000
Non-cash goodwill impairment charge										0	0	0
Non-cash expense for impairment of identifiable intangible assets		2,428,000	$ 0	$ 0	$ 0	0	$ 0	$ 0	$ 0	2,428,000	0	1,471,000
Non-cash impairment charge of finite-lived intangible assets										0	0	0
Accumulated impairment charge												210,600,000
Indefinite-lived intangible asset acquired										$ 57,900,000	8,700,000
Amortization periods										10 years 6 months
Amortization of identifiable intangible assets										$ 40,908,000	37,895,000	37,966,000
Domestic Segments
Goodwill and Intangible Assets[Line Items]
Perpetual growth rate used for annual testing	2.70%
United States Industrial Services
Goodwill and Intangible Assets[Line Items]
Goodwill		384,639,000				384,639,000				$ 384,639,000	384,639,000	384,639,000
Goodwill allocated										39.30%
Weighted average cost of capital used in annual testing for impairment	11.50%
Accumulated impairment charge												71,100,000
United States Building Services
Goodwill and Intangible Assets[Line Items]
Goodwill		244,793,000				228,637,000				$ 244,793,000	228,637,000	228,385,000
Goodwill allocated										25.00%
Weighted average cost of capital used in annual testing for impairment	11.00%
Accumulated impairment charge												139,500,000
Domestic Construction
Goodwill and Intangible Assets[Line Items]
Weighted average cost of capital used in annual testing for impairment	11.40%
United States Mechanical Construction And Facilities Services
Goodwill and Intangible Assets[Line Items]
Goodwill		226,596,000				226,071,000				$ 226,596,000	226,071,000	217,255,000
Goodwill allocated										23.10%
United States Electrical Construction And Facilities Services
Goodwill and Intangible Assets[Line Items]
Goodwill		$ 123,600,000				$ 3,823,000				$ 123,600,000	3,823,000	3,823,000
Goodwill allocated										12.60%
Developed technology/Vendor network
Goodwill and Intangible Assets[Line Items]
Amortization periods										10 years 6 months
Customer relationships
Goodwill and Intangible Assets[Line Items]
Amortization periods										10 years 3 months
Non-competition agreements
Goodwill and Intangible Assets[Line Items]
Amortization periods										1 year 3 months
Trade names (amortized)
Goodwill and Intangible Assets[Line Items]
Amortization periods										10 years 6 months
Trade names (unamortized)
Goodwill and Intangible Assets[Line Items]
Non-cash expense for impairment of identifiable intangible assets										$ 2,400,000	$ 0	$ 1,500,000