Amount of deferred payments by the acquirer as part of consideration transferred in a business combination.

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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 first period of time following the current date, 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 daily cash collateral, for a potential additional 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 first 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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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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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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Amount of amortization expense attributable to debt issuance costs.

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

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

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No definition available.

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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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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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No definition available.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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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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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Note 8 - Debt (Details Textual)				3 Months Ended		6 Months Ended
Note 8 - Debt (Details Textual)	Apr. 03, 2020 USD ($)	Apr. 03, 2019 USD ($)	Apr. 03, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Interest Expense, Debt				$ 3,000,000	$ 800,000	$ 3,100,000	$ 1,700,000
Amortization of Debt Issuance Costs				500,000
Payment for Debt Extinguishment or Debt Prepayment Cost				800,000		800,000
Tealstone Construction [Member]
Payments to Acquire Businesses, Gross			$ 55,000,000
Fair Value Inputs, Discount Rate			12.00%
Business Combination, Consideration Transferred, Deferred Payments			$ 7,211,000
Accretion Expense				300,000		300,000
Business Combination, Consideration Transferred, Liabilities Incurred			4,436,000
Tealstone Construction [Member] \| Scenario, Forecast [Member]
Payments to Acquire Businesses, Gross	$ 7,500,000	$ 2,500,000
Revolving Credit Facility [Member]
Long-term Line of Credit								$ 0
Warrants to the Lenders Under the Loan Agreement [Member]
Warrants and Rights Outstanding			3,500,000	3,500,000		3,500,000
Senior Secured Term Loans [Member]
Debt Issuance Costs, Net				9,869,000		9,869,000		803,000
Long-term Debt, Fair Value				85,000,000		85,000,000		3,500,000
Notes Payable for Transportation and Construction Equipment [Member]
Notes Payable, Noncurrent				$ 2,100,000		$ 2,100,000		$ 2,700,000
Notes Payable for Transportation and Construction Equipment [Member] \| Minimum [Member]
Debt Instrument, Term						3 years
Debt Instrument, Interest Rate, Stated Percentage				3.15%		3.15%
Notes Payable for Transportation and Construction Equipment [Member] \| Maximum [Member]
Debt Instrument, Term						5 years
Debt Instrument, Interest Rate, Stated Percentage				6.92%		6.92%
Wilmington Trust, National Association [Member] \| Loan and Security Agreement [Member] \| Senior Secured Term Loans [Member]
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			3.1
Debt Instrument, Financial Covenants, Maximum Ratio of Secured Indebtedness to EBITDA, Period Two			1.8
Debt Instrument, Financial Covenants, Minimum Daily Cash Collateral, Period One			$ 10,000,000
Debt Instrument, Financial Covenants, Minimum Daily Cash Collateral, Period Two			15,000,000
Debt Instrument, Financial Covenants, Minimum Daily Cash Collateral, Potential Additional Period			18,000,000
Debt Instrument, Financial Covenants, Minimum Rolling Four Quarter Gross Margin in Contract Backlog, Period One			60,000,000
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
Debt Issuance Costs, Net				$ 10,400,000		$ 10,400,000
Debt Instrument, Term						5 years
Amortization of Debt Issuance Costs						$ 500,000
Wilmington Trust, National Association [Member] \| Loan and Security Agreement [Member] \| Senior Secured Term Loans [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate			8.75%