XML 66 R40.htm IDEA: XBRL DOCUMENT
v3.19.3

Consolidated 50% Owned Subsidiaries - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018 | Dec. 31, 2018
Noncontrolling Interest [Line Items] |  |  |  |  |
Ownership interest in subsidiaries | 50.00% |  | 50.00% |  |
Members’ interest subject to mandatory redemption | $ 40,000 |  | $ 40,000 |  | $ 40,000
Total disability insurance policies, per policy amount | 20,000 |  | 20,000 |  |
Myers |  |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |  |
Net accumulated earnings | 5,500 | $ 5,100 | 8,200 | $ 10,400 |
Myers | Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |  |
Members’ interest subject to mandatory redemption | $ 20,000 |  | $ 20,000 |  |

X
- Definition Consolidated Entities, Ownership Percentage + References No definition available. + Details
Name: | strl_ConsolidatedEntitiesOwnershipPercentage
Namespace Prefix: | strl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Death And Disability Insurance Policies, Per Policy Amount + References No definition available. + Details
Name: | strl_DeathAndDisabilityInsurancePoliciesPerPolicyAmount
Namespace Prefix: | strl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The Member's interest subject to mandatory redemption. + References No definition available. + Details
Name: | strl_MembersInterestSubjectToMandatoryRedemption
Namespace Prefix: | strl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount before tax of income (loss) of subsidiary attributable to the parent entity. + References No definition available. + Details
Name: | us-gaap_IncomeLossFromSubsidiariesBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_MinorityInterestLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=strl_MyersMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |