Represents the information pertaining to the earn out payment made to the acquired entity each year under agreement.

No definition available.

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Represents the information pertaining to the estimated percentage of the potential earn out as determined by the acquiring entity.

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No definition available.

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Represents the information pertaining to the gain (loss) on change in the value of contingent consideration for the period.

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No definition available.

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Represents the information pertaining to the minimum operating income threshold to be earned during the first year.

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No definition available.

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Represents the information pertaining to the minimum operating income threshold to be earned during the second year.

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No definition available.

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Represents the information pertaining to the operating income to be earned to receive maximum consideration during the first year.

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No definition available.

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Represents the information pertaining to the operating income to be earned to receive maximum consideration during the second year.

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No definition available.

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Represents the earn out period for operating income projection used for fair value measurement.

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No definition available.

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Represents the number of employees acquired in the acquisition.

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No definition available.

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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.

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No definition available.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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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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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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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.

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Acquisitions and Divestitures - Narrative (Details)	3 Months Ended					9 Months Ended		12 Months Ended
Acquisitions and Divestitures - Narrative (Details)	Jul. 01, 2018 USD ($)	Apr. 01, 2018 USD ($) employee	Dec. 31, 2017 USD ($) employee	Apr. 02, 2017 USD ($) employee	Mar. 27, 2016 USD ($)	Jul. 01, 2018 USD ($)	Jul. 02, 2017 USD ($)	Oct. 01, 2017 USD ($)	Oct. 02, 2016 USD ($)
Mergers and Acquisitions
Contingent earn-out liability	$ 31,200,000					$ 31,200,000
Aggregate maximum of contingent consideration	48,500,000					48,500,000
Proceeds from sale of divested business						36,250,000	$ 0
Increase (decrease) in contingent consideration	200,000					2,100,000	(7,100,000)
Gain (loss) on change in contingent consideration	(200,000)					$ (2,100,000)	7,100,000
Minimum
Mergers and Acquisitions
Earn-out period						2 years
Minimum \| Existing customer contracts
Mergers and Acquisitions
Useful life of intangible assets						1 year
Minimum \| Trade names
Mergers and Acquisitions
Useful life of intangible assets						3 years
Maximum
Mergers and Acquisitions
Earn-out period						3 years
Maximum \| Existing customer contracts
Mergers and Acquisitions
Useful life of intangible assets						10 years
Maximum \| Trade names
Mergers and Acquisitions
Useful life of intangible assets						5 years
Norman Disney & Young
Mergers and Acquisitions
Number of employees acquired in acquisition \| employee		700
Fair value of acquisition purchase price		$ 56,100,000
Cash paid to the former owners		46,900,000
Amount held in escrow		1,600,000
Contingent earn-out liability		7,600,000
Aggregate maximum of contingent consideration		$ 20,200,000
Earn-out period		3 years
Glumac
Mergers and Acquisitions
Number of employees acquired in acquisition \| employee			300
Fair value of acquisition purchase price			$ 38,400,000
Cash paid to the former owners			20,000,000
Contingent earn-out liability			18,400,000
Aggregate maximum of contingent consideration			$ 20,000,000
Earn-out period			3 years
Eco Logical Australia
Mergers and Acquisitions
Number of employees acquired in acquisition \| employee				160
Fair value of acquisition purchase price				$ 9,900,000
Cash paid to the former owners				8,300,000
Contingent earn-out liability				1,600,000
Aggregate maximum of contingent consideration				$ 1,700,000
Earn-out period				2 years
INDUS
Mergers and Acquisitions
Contingent earn-out liability				$ 0	$ 4,700,000				$ 4,900,000
Aggregate maximum of contingent consideration					$ 8,000,000
Earn-out period					2 years
Increase (decrease) in contingent consideration							(5,000,000)
Potential earn-out to be paid each year					$ 4,000,000
Estimated potential earn-out (as a percent)					50.00%				59.00%
Minimum operating income threshold to earn contingent consideration during year one				3,200,000	$ 3,200,000
Minimum operating income threshold to earn contingent consideration during year two				3,600,000	3,600,000
Operating income to earn maximum consideration during the first year					3,600,000
Operating income to earn maximum consideration during the second year					$ 4,000,000
Gain (loss) on change in contingent consideration				$ 5,000,000			5,000,000
CEG
Mergers and Acquisitions
Increase (decrease) in contingent consideration							(2,100,000)
Gain (loss) on change in contingent consideration							$ 2,100,000
Non-core field services business \| Disposed of by sale
Mergers and Acquisitions
Proceeds from sale of divested business	30,200,000
Revenue from wired and fiber optic communication and infrastructure projects								$ 70,000,000
Loss on disposition of business	$ 3,400,000					$ 3,400,000