Business Combination, Consideration Transferred, Working Capital

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Debt Instrument, Covenants, Additional Increase Provision

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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 liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Value of input used to measure contingent consideration liability from business combination.

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

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- Definition

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

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Face (par) amount of debt instrument at time of issuance.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

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

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Number of shares of stock issued during the period pursuant to acquisitions.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Subsequent Events (Details) shares in Thousands	Oct. 02, 2019 USD ($) shares	Oct. 21, 2019 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Subsequent Event [Line Items]
Goodwill			$ 85,231,000	$ 85,231,000
LK Gregory Construction, Plateau Excavation and DeWitt Excavation \| Subsequent Event
Subsequent Event [Line Items]
Aggregate consideration	$ 411,608,000
Payments to acquire businesses	$ 375,000,000
Common stock issued in acquisition (in shares) \| shares	1,245
Subordinated promissory note issued in acquisition	$ 10,000,000
Preliminary target working capital adjustment	$ 10,413,000
Net tangible assets acquired		$ 98,771,000
Intangible assets acquired		162,675,000
Goodwill		$ 150,162,000
Measurement Input, Discount Rate \| LK Gregory Construction, Plateau Excavation and DeWitt Excavation \| Subsequent Event
Subsequent Event [Line Items]
Subordinated promissory note discount rate	0.08
Senior Secured Debt \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument face amount	$ 475,000,000
Loans Payable \| Senior Secured First Lien Term Loan \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument face amount	400,000,000
Option to increase aggregate principal amount	100,000,000
Revolving Credit Facility [Member] \| Subsequent Event
Subsequent Event [Line Items]
Aggregate principal amount	75,000,000
Letter of Credit \| Subsequent Event
Subsequent Event [Line Items]
Aggregate principal amount	75,000,000
Swing Line Loan \| Subsequent Event
Subsequent Event [Line Items]
Aggregate principal amount	$ 15,000,000