Acquisitions (Purchase Price Allocation) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Apr. 30, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Goodwill	$ 3,243	$ 3,272		$ 2,953	$ 2,970
National Pump
Business Acquisition [Line Items]
Accounts receivable, net of allowance for doubtful accounts			$ 44
Inventory			19
Deferred taxes			6
Intangibles			289
Other assets			1
Total identifiable assets acquired			541
Current liabilities			(25)
Total liabilities assumed			(25)
Net identifiable assets acquired			516
Goodwill			333
Net assets acquired			849
Accounts receivable, gross			47
Accounts receivable, allowance for doubtful accounts			3
Rental Equipment | National Pump
Business Acquisition [Line Items]
Rental equipment and Property and equipment			172
Property and Equipment | National Pump
Business Acquisition [Line Items]
Rental equipment and Property and equipment			$ 10