Note 2 - Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Accumulated depreciation and amortization	$ (606,503)	$ (576,345)
Total	1,279,931	1,184,053
Land [Member]
Property and equipment, gross	137,416	134,873
Building and Building Improvements [Member]
Property and equipment, gross	$ 474,106	434,049
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	$ 34,350	27,165
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	$ 82,594	73,578
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	$ 73,846	67,330
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	$ 99,127	92,385
Transportation Equipment [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	3 years
Transportation Equipment [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	15 years
Vehicles [Member]
Property and equipment, gross	$ 968,121	914,708
Vehicles [Member] \| Minimum [Member]
Property and equipment, estimated life (Year)	1 year
Vehicles [Member] \| Maximum [Member]
Property and equipment, estimated life (Year)	8 years
Construction in Progress [Member]
Property and equipment, gross	$ 16,874	$ 16,310

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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