The parent entity's majority interest in net assets of the subsidiary, expressed as a percentage.

No definition available.

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Namespace Prefix:	sgrp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents number of specialist provided by a related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Represents number of vehicles leased under lease arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents number of vehicles subleased.

+ References

No definition available.

+ Details

Name:	sgrp_NumberOfVehiclesSubleased
Namespace Prefix:	sgrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percent of service provided by related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgrp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership that has been transferred to related parties.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgrp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of ownership by a related person in a related entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	sgrp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Total costs related to services rendered by an entity during the reporting period.

+ 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 210.5-03.2(d))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LesseeLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

+ References

No definition available.

+ Details

Name:	us-gaap_RelatedPartyTransactionRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_MrBrownMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_SBSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=sgrp_DomesticFieldManagementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=sgrp_DomesticMerchandisingSpecialistsFieldForceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=sgrp_CostPlusFeeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_SasMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=sgrp_AdministrativeServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_SbsAndSasMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_NMSMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_NRSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=sgrp_Plus2CompensationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_CMRMeridienMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseArrangementTypeAxis=sgrp_LeaseArrangementWithMcptMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_MrBrianMasonMrGarryBristowAndMrAdrianWingfieldMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_MrMasonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_NDSMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_MrAndMsYilmazMember
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Data Type:	na
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Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_SPARTodopromoMember
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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_MrJuanFMedinaDomenzainMember
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Data Type:	na
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- Details

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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sgrp_AffinityInsuranceMember
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Data Type:	na
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Note 5 - Related-Party Transactions (Details Textual)				9 Months Ended
Note 5 - Related-Party Transactions (Details Textual)	Dec. 01, 2014	Aug. 01, 2013	Jan. 01, 2004	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jan. 02, 2015
Mr. Brown [Member]
Percentage Ownership Transferred To Related Parties						84.00%
SBS [Member] \| Domestic Field Management [Member]
Number Of Specialists Provided By Related Party				9,000
SBS [Member] \| Domestic Merchandising Specialists Field Force [Member]
Percent Of Service Provided By Related Party				83.00%	80.00%
SBS [Member] \| Cost Plus Fee [Member]
Related Party Transaction, Rate	2.94%
SAS [Member] \| Domestic Field Management [Member]
Percent Of Service Provided By Related Party				90.00%	93.00%
SAS [Member] \| Administrative Services [Member]
Number Of Specialists Provided By Related Party				56
SBS And SAS [Member] \| Domestic Field Management [Member]
Cost of Services				$ 19,500,000	$ 20,500,000
SBS And SAS [Member] \| Cost Plus Fee [Member]
Related Party Transaction, Rate			4.00%
N M S [Member]
Majority Interest Ownership Percentage By Parent				51.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%
NRS [Member] \| Domestic Merchandising Specialists Field Force [Member]
Number Of Specialists Provided By Related Party		317
Percent Of Service Provided By Related Party				5.00%	9.00%
NRS [Member] \| Plus2 Compensation [Member]
Related Party Transaction, Rate				2.00%
Related Party Transaction, Amounts of Transaction				$ 20,000	$ 38,000
C M R Meridien [Member] \| Lease Arrangement With MCPT [Member]
Number Of Vehicles Subleased				2
Number Of Vehicles Leased				126
Lessee Leasing Arrangements, Operating Leases, Term of Contract				4 years
C M R Meridien [Member]
Majority Interest Ownership Percentage By Parent				51.00%
Mr. Brian Mason Mr. Garry Bristow And Mr. Adrian Wingfield [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%
Mr. Mason [Member]
Related Party Ownership Percentage				50.00%
NDS [Member]
Majority Interest Ownership Percentage By Parent				51.00%
Mr And Ms Yilmaz [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%
Related Party Ownership Percentage				40.00%
SPAR Todopromo [Member]
Majority Interest Ownership Percentage By Parent				51.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%
Mr. Juan F. Medina Domenzain [Member] \| CON [Member]
Related Party Ownership Percentage				90.00%
Affinity Insurance [Member] \| Maximum [Member]
Noncontrolling Interest, Ownership Percentage by Parent				1.00%