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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For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

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Amount of expense for amortization of capitalized computer software costs.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amount of property and equipment
Property and equipment gross	$ 488.3	$ 365.9
Accumulated depreciation and amortization	177.1	140.3
Total property and equipment, net	311.2	225.6
Depreciation expense	42.5	35.1	$ 30.3
Land
Amount of property and equipment
Property and equipment gross	27.4	31.6
Buildings and leasehold improvements
Amount of property and equipment
Property and equipment gross	$ 87.3	41.2
Buildings and leasehold improvements \| Minimum
Amount of property and equipment
Estimated useful lives	3 years
Buildings and leasehold improvements \| Maximum
Amount of property and equipment
Estimated useful lives	40 years
Office equipment, furniture and fixtures
Amount of property and equipment
Property and equipment gross	$ 15.4	14.1
Office equipment, furniture and fixtures \| Minimum
Amount of property and equipment
Estimated useful lives	3 years
Office equipment, furniture and fixtures \| Maximum
Amount of property and equipment
Estimated useful lives	10 years
Computer equipment and software costs
Amount of property and equipment
Property and equipment gross	$ 140.7	118.9
Computer equipment and software costs \| Minimum
Amount of property and equipment
Estimated useful lives	3 years
Computer equipment and software costs \| Maximum
Amount of property and equipment
Estimated useful lives	10 years
Machinery, equipment and vehicles
Amount of property and equipment
Property and equipment gross	$ 217.5	160.1
Machinery, equipment and vehicles \| Minimum
Amount of property and equipment
Estimated useful lives	3 years
Machinery, equipment and vehicles \| Maximum
Amount of property and equipment
Estimated useful lives	40 years
Computer software costs
Computer software costs
Computer software costs	$ 94.5	91.4
Accumulated amortization	69.5	55.8
Computer software costs, net	25.0	35.6
Computer software costs	94.5	91.4
Amortization expense related to computer software costs	13.7	10.7	$ 9.8
Software development in progress
Computer software costs
Computer software costs	12.5	7.0
Computer software costs	12.5	7.0
Capital lease
Amount of property and equipment
Property and equipment gross	24.4	23.0
Accumulated depreciation and amortization	8.2	11.0
Total property and equipment, net	$ 16.2	$ 12.0