Note 9 - Commitments and Contingencies (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
SBS [Member]
Related Party Transaction, Reimbursement of Legal Expenses from Transaction with Related Party	$ 85,000	$ 354,000

The amount of legal expenses reimbursed by the company to the related party.

No definition available.

Name:	sgrp_RelatedPartyTransactionReimbursementOfLegalExpensesFromTransactionWithRelatedParty
Namespace Prefix:	sgrp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration