The amount reported in net expense that is less than the would be charges for period under the counter proposal.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Represents number of specialist provided by a related party.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents number of vehicles leased under lease arrangement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents number of vehicles subleased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

The percentage of the workforce provided by related parties.

+ References

No definition available.

+ Details

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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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Data Type:	num:percentItemType
Balance Type:	na
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- 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

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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

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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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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

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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

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-Name Accounting Standards Codification

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

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-Topic 850

-SubTopic 10

-Section 50

-Paragraph 4

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

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

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: 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

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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

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

- Details

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Name:	us-gaap_RelatedPartyTransactionAxis=sgrp_DomesticFieldManagementMember
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Data Type:	na
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Note 5 - Related-Party Transactions (Details)				3 Months Ended		6 Months Ended
Note 5 - Related-Party Transactions (Details)	Dec. 01, 2014	Aug. 01, 2013	Jan. 01, 2004	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jan. 02, 2015
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party (in Dollars)				$ 7,100,000	$ 8,163,000	$ 14,246,000	$ 15,835,000
Mr. Brown [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Percentage Ownership Transferred to Related Parties								84.00%
SBS [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Amount Reported in Net Expense that is Less than the Counter Proposal (in Dollars)						101,000
SBS [Member] \| Cost Plus Fee [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party Transaction, Rate	2.97%
SBS [Member] \| Legal Expense [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party (in Dollars)						$ 267,000	$ 265,000
SBS [Member] \| Domestic Field Management [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Number of Specialists Provided by Related Party						9,000
SBS [Member] \| Domestic Merchandising Specialists Field Force [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Percent of Service Provided by Related Party						84.00%	78.00%
SAS [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Amount Reported in Net Expense that is Less than the Counter Proposal (in Dollars)						$ 44,000
SAS [Member] \| Domestic Field Management [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Percent of Service Provided by Related Party						90.00%	93.00%
SAS [Member] \| Administrative Services [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Number of Specialists Provided by Related Party						56
SBS and SAS [Member] \| Cost Plus Fee [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party Transaction, Rate			4.00%
SBS and SAS [Member] \| Domestic Field Management [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Cost of Services (in Dollars)						$ 13,300,000	$ 13,700,000
NMS [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Majority Interest, Ownership Percentage by Parent				51.00%		51.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%		49.00%
NRS [Member] \| Domestic Merchandising Specialists Field Force [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Number of Specialists Provided by Related Party		294
Percent of Service Provided by Related Party						4.00%	10.00%
NRS [Member] \| Plus 2% Compensation [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party Transaction, Amounts of Transaction (in Dollars)						$ 11,000	$ 27,000
Related Party Transaction, Rate						2.00%
CMR Meridien [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Majority Interest, Ownership Percentage by Parent				51.00%		51.00%
Mr. Brian Mason, Mr. Garry Bristow, and Mr. Adrian Wingfield [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%		49.00%
Mr. Mason [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party, Ownership Percentage						50.00%
NDS [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Majority Interest, Ownership Percentage by Parent				51.00%		51.00%
Mr. and Ms. Yilmaz [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				49.00%		49.00%
Related Party, Ownership Percentage						40.00%
Lease Arrangement With MCPT [Member] \| CMR Meridien [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Number of Vehicles Subleased						2
Number of Vehicles Leased						126
Lessee Leasing Arrangements, Operating Leases, Term of Contract						4 years
Without Charge [Member] \| SBS and SAS [Member] \| Administrative Services [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Related Party Transaction, Amounts of Transaction (in Dollars)						$ 65,000	$ 65,000
Maximum [Member] \| Affinity [Member]
Note 5 - Related-Party Transactions (Details) [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent				1.00%		1.00%