Note 1. Summary of restaurant operations revenues (Details) - Consolidated - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Sep. 24, 2014	Sep. 25, 2013
Net sales	$ 210,256	$ 200,407	$ 799,660	$ 759,889	$ 736,968
Franchise royalties and fees	4,076	3,177	16,428	15,032	11,741
Other	1,316	858	3,650	3,234	3,210
Total revenue from restaurant operations	$ 215,648	$ 204,442	$ 819,738	$ 778,155	$ 751,919

Revenue from multiple-deliverable arrangements that include licensing fees and maintenance revenue. Licensing revenue is consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Maintenance revenue is derived from maintenance services provided under contracts or arrangements with clients. Services may include the maintenance of software, plant and equipment, and facilities.

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