Represents the amount of salary to be annually paid to employee(s) of the company.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents value of the non-monetary award granted to an individual.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Represents the term for the shareholder return in the incentive plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	strl_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of the incentive plan that is based on service completion.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of the plan that is based on shareholder return.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 710

-SubTopic 10

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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Note 9 - Stockholders' Equity (Details) - USD ($)			1 Months Ended	3 Months Ended		6 Months Ended
Note 9 - Stockholders' Equity (Details) - USD ($)	Mar. 09, 2015	Jan. 01, 2015	May. 31, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Note 9 - Stockholders' Equity (Details) [Line Items]
Allocated Share-based Compensation Expense				$ 300,000	$ 200,000	$ 500,000	$ 400,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				3,600,000		$ 3,600,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition						2 years 292 days
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options				0	$ 0	$ 0	$ 0
Proceeds from Stock Options Exercised				$ 0		$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)				0	0	0	0
Chief Executive Officer [Member]
Note 9 - Stockholders' Equity (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	600,000
Deferred Compensation Arrangement with Individual, Maximum Contractual Term	3 years
Annual Salary to be Paid to Employee	$ 1
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Deferred Compensation Arrangement with Individual, Award Value			$ 2,500,000
D.A. Davidson & Co. [Member]
Note 9 - Stockholders' Equity (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in Shares)				900,000		900,000
Long Term Incentive Plan [Member]
Note 9 - Stockholders' Equity (Details) [Line Items]
Allocated Share-based Compensation Expense				$ 100,000		$ 200,000
Percentage of Incentive Plan Based on Service Completion		50.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period		3 years
Percentage of Incentive Plan Based on Shareholder Return		50.00%
Incentive Plan, Term for Shareholder Return		3 years