XML 54 R41.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Employee Benefit Plans (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2017
Defined Benefit Plan [Abstract] |
Schedule of Defined Contribution Plan | The following table presents our participation in these plans (amounts in thousands):
| Pension Plan Employer |  | Pension Protection Act (“PPA”) Certified Zone Status 1 |  | FIP / RP Status Pending/Implemented 2 |  | Contributions |  | Surcharge Imposed |  | Expiration Date of Collective Bargaining Agreement 3
Pension Trust Fund | Identification Number |  | 2017 |  | 2016 |  |  | 2017 |  | 2016 |  | 2015 |  |
Pension Trust Fund for Operating Engineers Pension Plan | 94-6090764 |  | Red |  | Red |  | Yes |  | $ | 2,477 |  |  | $ | 2,145 |  |  | $ | 2,151 |  |  | No |  | Various
Laborers Pension Trust for Northern California | 94-6277608 |  | Yellow |  | Yellow |  | Yes |  | 953 |  |  | 1,059 |  |  | 966 |  |  | No |  | Various
Carpenter Funds Administrative Office | 94-6050970 |  | Red |  | Red |  | Yes |  | 727 |  |  | 636 |  |  | 842 |  |  | No |  | Various
Cement Mason Pension Trust Fund For Northern California | 94-6277669 |  | Yellow |  | Yellow |  | Yes |  | 423 |  |  | 311 |  |  | 371 |  |  | No |  | Various
All other funds 4 |  |  |  |  |  |  |  |  | 8,006 |  |  | 8,487 |  |  | 10,204 |  |  |  |  |
|  |  |  |  |  |  | Total Contribution: |  | $ | 12,586 |  |  | $ | 12,638 |  |  | $ | 14,534 |  |  |  |  |
1 The most recent PPA zone status available in 2017 and 2016 is for the plan’s year-end during 2016 and 2015, respectively. The zone status is based on information that we received from the plan and is certified by the plan’s actuary. Among other factors, plans in the red zone are generally less than 65 percent funded, plans in the orange zone are less than 80 percent funded and have an Accumulated Funding Deficiency in the current year or projected into the next six years, plans in the yellow zone are less than 80 percent funded and plans in the green zone are at least 80 percent funded. 2 Indicates whether the plan has a financial improvement plan (“FIP”) or a rehabilitation plan (“RP”) which is either pending or has been implemented. 3 Lists the expiration date(s) of the collective-bargaining agreement(s) to which the plans are subject. 4 These funds include multi-employer plans for pensions and other employee benefits. The total individually insignificant multi-employer pension costs contributed were $1.5 million, $1.2 million and $1.5 million for 2017, 2016 and 2015, respectively, and are included in the contributions to all other funds along with contributions to other types of benefit plans. Other employee benefits include certain coverage for medical, prescription drug, dental, vision, life and accidental death and dismemberment, disability and other benefit costs.

X
- Definition Represents the schedule of defined contribution plan. + References No definition available. + Details
Name: | strl_ScheduleofDefinedContributionPlanTableTextBlock
Namespace Prefix: | strl_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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