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v2.4.1.9

Note 1 - Summary of Business and Significant Accounting Policies (Details) (USD $) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership Interest In Subsidiary |  |  |  |  |  |  |  |  | 50.00%strl_OwnershipInterestInSubsidiary |  |
Estimated Construction Gross Profit, Before Tax |  |  |  |  |  |  |  |  | $ 9,100,000 strl_EstimatedConstructionGrossProfitBeforeTax | $ 57,600,000 strl_EstimatedConstructionGrossProfitBeforeTax | $ 4,900,000 strl_EstimatedConstructionGrossProfitBeforeTax
Estimated Construction Gross Profit Per Diluted Share (in Dollars per share) |  |  |  |  |  |  |  |  | $ 0.50 strl_EstimatedConstructionGrossProfitPerDilutedShare | $ 3.46 strl_EstimatedConstructionGrossProfitPerDilutedShare | $ 0.32 strl_EstimatedConstructionGrossProfitPerDilutedShare
Estimated Construction Gross Profit, Net Of Tax |  |  |  |  |  |  |  |  |  |  | 5,300,000 strl_EstimatedConstructionGrossProfitNetOfTax
Billings in Excess of Cost, Current | 25,649,000 us-gaap_BillingsInExcessOfCostCurrent |  |  |  | 31,576,000 us-gaap_BillingsInExcessOfCostCurrent |  |  |  | 25,649,000 us-gaap_BillingsInExcessOfCostCurrent | 31,576,000 us-gaap_BillingsInExcessOfCostCurrent |
Revenues | 153,611,000 us-gaap_Revenues | 189,275,000 us-gaap_Revenues | 194,806,000 us-gaap_Revenues | 134,538,000 us-gaap_Revenues | 125,916,000 us-gaap_Revenues | 185,935,000 us-gaap_Revenues | 133,350,000 us-gaap_Revenues | 111,035,000 us-gaap_Revenues | 672,230,000 us-gaap_Revenues | 556,236,000 us-gaap_Revenues | 630,507,000 us-gaap_Revenues
Mortgage Loans on Real Estate, Number of Loans |  |  |  |  |  |  |  |  | 1 us-gaap_MortgageLoansOnRealEstateNumberOfLoans | 1 us-gaap_MortgageLoansOnRealEstateNumberOfLoans |
Mortgage Loans on Real Estate | 200,000 us-gaap_MortgageLoansOnRealEstate |  |  |  | 100,000 us-gaap_MortgageLoansOnRealEstate |  |  |  | 200,000 us-gaap_MortgageLoansOnRealEstate | 100,000 us-gaap_MortgageLoansOnRealEstate |
Mortgage Loans on Real Estate, Interest Rate |  |  |  |  |  |  |  |  | 3.50%us-gaap_MortgageLoansOnRealEstateInterestRate | 3.50%us-gaap_MortgageLoansOnRealEstateInterestRate |
Notes Payable, Noncurrent | 3,300,000 us-gaap_LongTermNotesPayable |  |  |  |  |  |  |  | 3,300,000 us-gaap_LongTermNotesPayable |  |
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum |  |  |  |  |  |  |  |  | 3.12%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum |  |
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum |  |  |  |  |  |  |  |  | 6.29%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum |  |
Contract Receivable Retainage | 16,400,000 us-gaap_ContractReceivableRetainage |  |  |  | 18,300,000 us-gaap_ContractReceivableRetainage |  |  |  | 16,400,000 us-gaap_ContractReceivableRetainage | 18,300,000 us-gaap_ContractReceivableRetainage |
Contract Receivable | 5,000,000 us-gaap_AccountsReceivableBilledForLongTermContractsOrPrograms |  |  |  | 7,800,000 us-gaap_AccountsReceivableBilledForLongTermContractsOrPrograms |  |  |  | 5,000,000 us-gaap_AccountsReceivableBilledForLongTermContractsOrPrograms | 7,800,000 us-gaap_AccountsReceivableBilledForLongTermContractsOrPrograms |
Interest Income from Contracts Receivable |  |  |  |  |  |  |  |  | 400,000 strl_InterestIncomeFromContractsReceivable | 300,000 strl_InterestIncomeFromContractsReceivable | 100,000 strl_InterestIncomeFromContractsReceivable
Allowance for Doubtful Accounts Receivable, Write-offs |  |  |  |  |  |  |  |  | 0 us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs |  | 0 us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Inventory, Net | 7,401,000 us-gaap_InventoryNet |  |  |  | 6,189,000 us-gaap_InventoryNet |  |  |  | 7,401,000 us-gaap_InventoryNet | 6,189,000 us-gaap_InventoryNet |
Depreciation |  |  |  |  |  |  |  |  | 18,200,000 us-gaap_Depreciation | 18,600,000 us-gaap_Depreciation | 19,000,000 us-gaap_Depreciation
Capitalized Debt Fees |  |  |  |  |  |  |  |  | 200,000 strl_CapitalizedDebtFees |  |
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums | 200,000 us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums |  |  |  | 200,000 us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums |  |  |  | 200,000 us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums | 200,000 us-gaap_UnamortizedLoanCommitmentAndOriginationFeesAndUnamortizedDiscountsOrPremiums |
Amortization of Financing Costs |  |  |  |  |  |  |  |  | 200,000 us-gaap_AmortizationOfFinancingCosts | 100,000 us-gaap_AmortizationOfFinancingCosts |
Number of Operating Segments |  |  |  |  |  |  |  |  | 1 us-gaap_NumberOfOperatingSegments |  |
Number of Reportable Segments |  |  |  |  |  |  |  |  | 1 us-gaap_NumberOfReportableSegments |  |
Other Operating Income [Member] | Contracts Assumed [Member] |  |  |  |  |  |  |  |  |  |  |
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Allowance for Doubtful Accounts Receivable, Write-offs |  |  |  |  |  |  |  |  |  | 1,800,000 us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = strl_ContractsAssumedMember / us-gaap_IncomeStatementLocationAxis = strl_OtherOperatingIncomeMember |
Allowance for Doubtful Accounts Receivable, Recoveries |  |  |  |  |  |  |  |  | 1,000,000 us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = strl_ContractsAssumedMember / us-gaap_IncomeStatementLocationAxis = strl_OtherOperatingIncomeMember |  |
Allowance for Doubtful Accounts Receivable |  |  |  |  | 1,800,000 us-gaap_AllowanceForDoubtfulAccountsReceivable / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = strl_ContractsAssumedMember / us-gaap_IncomeStatementLocationAxis = strl_OtherOperatingIncomeMember |  |  |  |  | 1,800,000 us-gaap_AllowanceForDoubtfulAccountsReceivable / us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis = strl_ContractsAssumedMember / us-gaap_IncomeStatementLocationAxis = strl_OtherOperatingIncomeMember |
Change Orders Not Approved By Customer [Member] |  |  |  |  |  |  |  |  |  |  |
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Billings in Excess of Cost, Current | 3,500,000 us-gaap_BillingsInExcessOfCostCurrent / us-gaap_FairValueByLiabilityClassAxis = strl_ChangeOrdersNotApprovedByCustomerMember |  |  |  | 0 us-gaap_BillingsInExcessOfCostCurrent / us-gaap_FairValueByLiabilityClassAxis = strl_ChangeOrdersNotApprovedByCustomerMember |  |  |  | 3,500,000 us-gaap_BillingsInExcessOfCostCurrent / us-gaap_FairValueByLiabilityClassAxis = strl_ChangeOrdersNotApprovedByCustomerMember | 0 us-gaap_BillingsInExcessOfCostCurrent / us-gaap_FairValueByLiabilityClassAxis = strl_ChangeOrdersNotApprovedByCustomerMember |
Claims [Member] |  |  |  |  |  |  |  |  |  |  |
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | $ 0 us-gaap_Revenues / us-gaap_StatementScenarioAxis = strl_ClaimsMember | $ 0 us-gaap_Revenues / us-gaap_StatementScenarioAxis = strl_ClaimsMember | $ 0 us-gaap_Revenues / us-gaap_StatementScenarioAxis = strl_ClaimsMember
Greater Than [Member] |  |  |  |  |  |  |  |  |  |  |
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership Interest In Joint Venture |  |  |  |  |  |  |  |  | 50.00%strl_OwnershipInterestInJointVenture / us-gaap_RangeAxis = strl_GreaterThanMember |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue Recognition Percentage of Completion Range |  |  |  |  |  |  |  |  | 12 months |  |
Debt Instrument Payment Term |  |  |  |  |  |  |  |  | 3 years |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Note 1 - Summary of Business and Significant Accounting Policies (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue Recognition Percentage of Completion Range |  |  |  |  |  |  |  |  | 36 months |  |
Debt Instrument Payment Term |  |  |  |  |  |  |  |  | 5 years |  |

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- Definition Indicates the number of mortgages under each classification. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule IV) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29.3) -URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule IV -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 29 -Paragraph 3 -Article 12 + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 + Details
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- Definition Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533 + Details
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