Note 15 - Other Supplemental Information - Summary of Other Supplemental Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Revenues	$ 1,931,473	$ 1,729,031
Operating earnings (loss)	127,568	104,962
Total assets	1,007,474	848,266
Income taxes	28,221	43,893
Interest	11,714	9,489
Increases in capital lease obligations	1,919	1,235
Rent expense	32,045	28,977
Franchisor Operations [Member]
Operating earnings (loss)	37,709	33,960
Depreciation and amortization	5,893	5,030
Total assets	128,627	109,889
Franchisor Operations [Member] \| Franchisor [Member]
Revenues	132,079	122,620
Franchisor Operations [Member] \| Franchise [Member]
Revenues	$ 4,496	$ 3,118

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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