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Represents the maximum incurrence of net capital expenditures during each of four consecutive fiscal quarters under the financial covenants pursuant to a debt instrument.

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Represents the maximum ratio of secured indebtedness to EBITDA, for a certain specified first period of time following the current date, under the financial covenants pursuant to a debt instrument.

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Represents the maximum ratio of secured indebtedness to EBITDA, for a certain specified second period of time following the current date, under the financial covenants pursuant to a debt instrument.

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Represents the minimum bonding capacity under the financial covenants pursuant to a debt instrument.

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Represents the minimum daily cash collateral, for a certain specified second period of time following the current date, under the financial covenants pursuant to a debt instrument.

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Represents the minimum EBITDA during each four consecutive fiscal quarters, for a certain specified period of time following the current date, under the financial covenants pursuant to a debt instrument.

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Represents the minimum rolling four quarter gross margin in contract backlog, for a certain specified second period of time following the current date, under the financial covenants pursuant to a debt instrument.

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Deferred Cash Payments Due

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Represents the percentage of excess cash flow, plus accrued and unpaid interest thereon and a prepayment premium, required to be made quarterly to the lenders to prepay the loan.

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The amount of notes payable and deferred payments that an Entity incurred in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Promissory Note Issued

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Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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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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Debt - Narrative (Details)	3 Months Ended
Debt - Narrative (Details)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Notes and deferred payments to sellers, Tealstone acquisition
Debt Instrument [Line Items]
Promissory notes issued to the sellers	$ 5,000,000
Cash payments to the seller	9,900,000
Deferred payments	2,400,000
Deferred cash payments due	7,500,000
Notes and deferred payments to sellers	11,600,000
Accretion expense	$ 300,000	$ 300,000
Notes and deferred payments to sellers, Tealstone acquisition \| Measurement Input, Discount Rate
Debt Instrument [Line Items]
Fair value inputs, discount rate	0.12
Notes payable for transportation and construction equipment and other
Debt Instrument [Line Items]
Notes Payable	$ 474,000		$ 612,000
Notes payable, noncurrent	500,000		600,000
Senior secured term loans \| Oaktree facility \| Equipment-based facility
Debt Instrument [Line Items]
Oaktree Facility	71,602,000		$ 74,571,000
Senior secured term loans \| Term loan \| Loan and security agreement
Debt Instrument [Line Items]
Debt instrument face amount	$ 85,000,000
Loan prepayment offer required to make quarterly, percentage	75.00%
Debt instrument, financial covenants, maximum ratio of secured indebtedness to EBITDA, period one	2
Debt Instrument, financial covenants, maximum ratio of secured indebtedness to EBITDA, period two	1.8
Debt Instrument, financial covenants, minimum daily cash collateral, period two	$ 15,000,000
Debt Instrument, financial covenants, minimum rolling four quarter gross margin in contract backlog, period two	70,000,000
Debt instrument, financial covenants, maximum incurrence of net capital expenditures during each of four consecutive fiscal quarters	15,000,000
Debt instrument, financial covenants, minimum bonding capacity	1,000,000,000
Debt instrument, financial covenants, minimum EBITDA during each four consecutive fiscal quarters	$ 12,000,000
Senior secured term loans \| Term loan \| Loan and security agreement \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	8.75%
Notes payable for transportation and construction equipment and other \| Minimum
Debt Instrument [Line Items]
Debt instrument, term	3 years
Debt instrument, interest rate, stated percentage	2.99%
Notes payable for transportation and construction equipment and other \| Maximum
Debt Instrument [Line Items]
Debt instrument, term	5 years
Debt instrument, interest rate, stated percentage	6.92%