Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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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 intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount of gain (loss) on sale or disposal of other assets.

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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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The number of businesses acquired by the entity during the period.

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Amount of cash inflow from the sale of other assets as part of operating activities.

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Business Acquisitions and Divestitures (Narrative) (Details) $ / shares in Units, $ in Thousands			3 Months Ended	9 Months Ended
	Oct. 04, 2017 USD ($) $ / shares	May 15, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2017 USD ($) acquisition	Sep. 15, 2017	Aug. 04, 2017
Business Acquisition [Line Items]
Number of businesses acquired \| acquisition				3
Cost of acquired entity purchase price				$ 87,000
Goodwill acquired			$ 58,000	57,518
Other identifiable intangibles added			36,000
Energy Systems & Controls
Business Acquisition [Line Items]
Goodwill acquired				19,169
Proceeds from sale of other assets		$ 10,400
Pretax gain on sale of other asset		$ 9,400
Customer related intangibles
Business Acquisition [Line Items]
Intangible assets other than goodwill			$ 24,000	24,000
Weighted average useful life			15 years
Technology
Business Acquisition [Line Items]
Intangible assets other than goodwill			$ 8,000	$ 8,000
Weighted average useful life			7 years
Handshake Software, Inc.
Business Acquisition [Line Items]
Percentage of shares acquired						100.00%
Workbook Software A/S
Business Acquisition [Line Items]
Percentage of shares acquired					100.00%
Onvia, Inc. \| Subsequent Event
Business Acquisition [Line Items]
Cost of acquired entity purchase price	$ 70,000
Business acquisition, share price (in usd per share) \| $ / shares	$ 9.00