Note 2 - Significant Accounting Policies (Details Textual) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019
Depreciation, Total			$ 149,100,000	$ 140,300,000	$ 140,600,000
Amortization, Total			36,000,000	17,600,000	17,000,000
Capitalized Computer Software, Net, Ending Balance	$ 10,800,000	$ 31,900,000	10,800,000	31,900,000
Capitalized Computer Software, Amortization			21,700,000	3,400,000
Indefinite-Lived Franchise Rights	7,000,000	7,000,000	7,000,000	7,000,000
Goodwill, Impairment Loss	0
Advertising Expense			10,400,000	9,500,000	6,800,000
Capitalized Computer Software, Accumulated Amortization	8,300,000	20,000,000	8,300,000	20,000,000
Subsequent Event [Member] | Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset						$ 51,900,000
Operating Lease, Liability, Total						$ 51,900,000
Vehicles [Member]
Depreciation, Total			114,600,000	$ 107,900,000	$ 106,300,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Other Property, Plant, and Equipment, Net, Total	66,400,000		66,400,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Property, Plant, and Equipment Other, Accumulated Depreciation	44,600,000		44,600,000
Computer Software, Intangible Asset [Member]
Interest Costs Capitalized			357,600
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		$ 0
Finite-Lived Intangible Assets, Amortization Expense, Year Two	1,900,000		1,900,000
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	1,900,000		1,900,000
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1,900,000		1,900,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four	1,900,000		1,900,000
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 1,900,000		1,900,000
Components of ERP Platform Rquired Replacement [Member]
Capitalized Computer Software, Amortization			$ 19,900,000