Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 35

-Paragraph 1

-Subparagraph b

-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 25

-Paragraph 6

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- Definition

The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

+ References

No definition available.

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- Definition

Nominal volume used to calculate payments on a derivative instrument.

+ References

No definition available.

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- Definition

Specified interest rate, security price, commodity price, foreign exchange rate, index of prices or rates for a derivative contract measured in volume but not the derivative contract itself.

+ References

No definition available.

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Fair Value Measurements (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Apr. 30, 2014
National Pump
Derivatives, Fair Value [Line Items]
Contingent consideration		$ 76
Merger related costs
Derivatives, Fair Value [Line Items]
Change in contingent consideration	(27)
Diesel swap \| Fixed price swap contracts
Derivatives, Fair Value [Line Items]
Fixed price swap contract (in gallons)	10,600,000
Average contract price (in dollars per gallon)	3.22
Average forward price (in dollars per gallon)	2.92
Level 3 \| National Pump \| Accrued expenses and other liabilities
Derivatives, Fair Value [Line Items]
Contingent consideration	50
First earn-out payment \| National Pump
Derivatives, Fair Value [Line Items]
Contingent consideration	50
Second earn-out payment \| National Pump
Derivatives, Fair Value [Line Items]
Contingent consideration	$ 0