Note 2 - Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Accumulated depreciation and amortization	$ (576,345)	$ (514,929)
Total	1,184,053	1,159,595
Land [Member]
Property and equipment, gross	134,873	129,805
Building and Building Improvements [Member]
Property and equipment, gross	$ 434,049	404,679
Building and Building Improvements [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	10 years
Building and Building Improvements [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	39 years
Leasehold Improvements [Member]
Property and equipment, gross	$ 27,165	26,765
Leasehold Improvements [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	2 years
Leasehold Improvements [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	39 years
Machinery and Equipment [Member]
Property and equipment, gross	$ 73,578	65,694
Machinery and Equipment [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	5 years
Machinery and Equipment [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	20 years
Furniture and Fixtures [Member]
Property and equipment, gross	$ 67,330	63,475
Furniture and Fixtures [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	3 years
Furniture and Fixtures [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	15 years
Transportation Equipment [Member]
Property and equipment, gross	$ 92,385	81,158
Transportation Equipment [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	2 years
Transportation Equipment [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	15 years
Vehicles [Member]
Property and equipment, gross	$ 914,708	894,905
Vehicles [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	2 years
Vehicles [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	8 years
Construction in Progress [Member]
Property and equipment, gross	$ 16,310	$ 8,043

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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