Note 10 - Related-party Transactions (Details) - Transactions Between the Company and Affiliates (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Services provided by affiliates:
Services provided by affiliates	$ 30,147	$ 28,173
Field Merchandiser Services (SBS) [Member]
Services provided by affiliates:
Services provided by affiliates	21,848	19,716
Field Management Services [Member]
Services provided by affiliates:
Services provided by affiliates	4,380	4,837
Field Merchandiser Services NMA [Member]
Services provided by affiliates:
Services provided by affiliates	2,259	1,983
Office and Vehicle Rental (MPT) [Member]
Services provided by affiliates:
Services provided by affiliates	57	62
Vehicle Rental (MCPT) [Member]
Services provided by affiliates:
Services provided by affiliates	597	562
Field Management Services (NDS Tanitim) [Member]
Services provided by affiliates:
Services provided by affiliates	44	32
Field Merchandiser Services (NDS Reklam) [Member]
Services provided by affiliates:
Services provided by affiliates	$ 962	$ 981