v3.10.0.1

Basis of Presentation - Financial Statement Impact (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018	Dec. 31, 2017
Balance Sheet
Other assets	$ 393.9		$ 393.9		$ 379.0	$ 335.2
Deferred income taxes and other long-term tax liabilities, net	868.4		868.4		806.8	796.4
Retained earnings	4,430.9		4,430.9		4,185.9	4,152.5
Income Statement
Revenue	2,517.8	$ 2,526.7	4,945.2	$ 4,919.5
Cost of operations	1,577.2	1,557.4	3,047.0	3,041.5
Depreciation, amortization and depletion	255.5	258.3	518.6	508.2
Selling, general and administrative	252.9	262.9	514.0	516.4
Operating income	408.2	$ 425.5	812.4	$ 813.7
As Computed Excluding the Adoption of ASU 2014-09
Income Statement
Revenue	2,600.7		5,114.8
Cost of operations	1,658.7		3,213.8
Depreciation, amortization and depletion	256.9		521.4
Selling, general and administrative	252.8		514.4
Operating income	408.3		812.0
Accounting Standards Update 2014-09 | Effect of Change
Income Statement
Revenue	82.9		169.6
Cost of operations	81.5		166.8
Depreciation, amortization and depletion	1.4		2.8
Selling, general and administrative	(0.1)		0.4
Operating income	$ 0.1		$ (0.4)
Calculated under Revenue Guidance in Effect before Topic 606
Balance Sheet
Other assets						335.2
Deferred income taxes and other long-term tax liabilities, net						796.4
Retained earnings						$ 4,152.5
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Balance Sheet
Other assets					43.8
Deferred income taxes and other long-term tax liabilities, net					10.4
Retained earnings					$ 33.4

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The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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