The amount of accrued expenses assumed, which have been recognized as of the acquisition date.

No definition available.

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The amount of inventory and other assets recognized as of the acquisition date.

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Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method that are expected to be realized within one year or one operating cycle, whichever is longer, from the reporting date.

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The amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings which is expected to be collected within one year or the normal operating cycle, if longer.

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The cash outflow associated with the acquisitions of businesses or productive assets.

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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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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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Business Combinations - Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jun. 16, 2017	Jun. 30, 2016	Feb. 28, 2015
Business combinations
Cash paid for acquisitions		$ 66,205	$ 10,997	$ 22,302
Fair value of the assets acquired and the liabilities assumed
Intangible assets		21,125	3,000	3,850
Goodwill		153,374	127,226	124,161
Purchase price allocation adjustments		(121)
2017 Acquisition
Fair value of the assets acquired and the liabilities assumed
Accounts receivable		10,721
Costs and estimated earnings in excess of billings		580
Inventory and other assets		2,352
Property, plant and equipment		12,402
Intangible assets		21,125
Goodwill		26,269
Accounts payable		(3,380)
Billings in excess of costs and estimated earnings		(447)
Accrued expenses		(2,096)
Total		67,526
2016 Acquisition
Fair value of the assets acquired and the liabilities assumed
Accounts receivable			1,606
Inventory and other assets			64
Property, plant and equipment			2,133
Intangible assets			3,000
Goodwill			5,781
Accounts payable			(726)
Accrued expenses			(861)
Total			10,997
2015 Acquisitions
Fair value of the assets acquired and the liabilities assumed
Accounts receivable				2,734
Inventory and other assets				1,476
Property, plant and equipment				11,173
Intangible assets				3,850
Goodwill				5,152
Accounts payable				(743)
Accrued expenses				(1,340)
Total				22,302
Aevenia
Business combinations
Cash paid for acquisitions				$ 22,302
Coastal
Business combinations
Cash paid for acquisitions		27,519
Fair value of the assets acquired and the liabilities assumed
Property, plant and equipment					$ 4,000
Goodwill					$ 9,300
Engineering
Business combinations
Cash paid for acquisitions		2,315
FGC
Business combinations
Cash paid for acquisitions		36,492
Fair value of the assets acquired and the liabilities assumed
Property, plant and equipment		4,800
Goodwill		17,000
Northern
Business combinations
Cash paid for acquisitions		$ (121)	6,889
Fair value of the assets acquired and the liabilities assumed
Goodwill	$ 3,700
Cash	100
Purchase price allocation adjustments	$ (100)
Mueller
Business combinations
Cash paid for acquisitions			$ 4,108
Fair value of the assets acquired and the liabilities assumed
Property, plant and equipment						$ 2,000
Goodwill						$ 2,000
Aevenia
Fair value of the assets acquired and the liabilities assumed
Property, plant and equipment							$ 11,200
Goodwill							$ 5,200