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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.

No definition available.

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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.

No definition available.

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

No definition available.

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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.

No definition available.

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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.

No definition available.

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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.

No definition available.

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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.

No definition available.

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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.

No definition available.

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The cost of borrowed funds accounted for as interest that was charged against earnings during the period. And, includes amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values.

No definition available.

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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.

No definition available.

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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.

No definition available.

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

No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Amount of amortization expense attributable to debt issuance costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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.

No definition available.

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Period Type:	duration

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.

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_LineOfCredit
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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.

No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_PaymentsOfDebtExtinguishmentCosts
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_WarrantsAndRightsOutstanding
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Period Type:	instant

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Name:	us-gaap_ClassOfWarrantOrRightAxis=strl_WarrantsToTheLendersUnderTheLoanAgreementMember
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