Comprehensive Income (Loss) (Details 2) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reclassifications out of accumulated other comprehensive income
Cost of services rendered and products sold	$ (983)us-gaap_CostOfGoodsAndServicesSold	$ (924)us-gaap_CostOfGoodsAndServicesSold	$ (1,220)us-gaap_CostOfGoodsAndServicesSold	$ (1,196)us-gaap_CostOfGoodsAndServicesSold	$ (1,125)us-gaap_CostOfGoodsAndServicesSold
Interest expense	171us-gaap_InterestExpense	186us-gaap_InterestExpense	247us-gaap_InterestExpense	245us-gaap_InterestExpense	266us-gaap_InterestExpense
Interest and net investment income	(7)us-gaap_InvestmentIncomeNonoperating	(6)us-gaap_InvestmentIncomeNonoperating	(8)us-gaap_InvestmentIncomeNonoperating	(7)us-gaap_InvestmentIncomeNonoperating	(11)us-gaap_InvestmentIncomeNonoperating
Provision for income taxes	(26)us-gaap_IncomeTaxExpenseBenefit	(43)us-gaap_IncomeTaxExpenseBenefit	(43)us-gaap_IncomeTaxExpenseBenefit	8us-gaap_IncomeTaxExpenseBenefit	6us-gaap_IncomeTaxExpenseBenefit
Total reclassifications for the period	76us-gaap_NetIncomeLoss	489us-gaap_NetIncomeLoss	507us-gaap_NetIncomeLoss	714us-gaap_NetIncomeLoss	(46)us-gaap_NetIncomeLoss
Amount Reclassified from Accumulated Other Comprehensive Income
Reclassifications out of accumulated other comprehensive income
Total reclassifications for the period	(2)	1	1	14	13
Amount Reclassified from Accumulated Other Comprehensive Income \| Fuel swap contracts
Reclassifications out of accumulated other comprehensive income
Cost of services rendered and products sold			(1)	(2)	(10)
Parent Issuer
Reclassifications out of accumulated other comprehensive income
Interest and net investment income					(7)
Provision for income taxes					(3)
Total reclassifications for the period			507	714	(46)
Unrealized Losses on Derivatives \| Amount Reclassified from Accumulated Other Comprehensive Income
Reclassifications out of accumulated other comprehensive income
Net losses on derivatives		3	4	20	28
Provision for income taxes		1	2	8	11
Total reclassifications for the period		2	2	12	17
Unrealized Losses on Derivatives \| Amount Reclassified from Accumulated Other Comprehensive Income \| Fuel swap contracts
Reclassifications out of accumulated other comprehensive income
Cost of services rendered and products sold		(2)
Unrealized Losses on Derivatives \| Amount Reclassified from Accumulated Other Comprehensive Income \| Interest rate swap contracts
Reclassifications out of accumulated other comprehensive income
Interest expense		5	5	22	38
Unrealized Gains on Available-for-Sale Securities \| Amount Reclassified from Accumulated Other Comprehensive Income
Reclassifications out of accumulated other comprehensive income
Interest and net investment income	(4)	(1)	(2)	3	(6)
Provision for income taxes	(2)		(1)	1	(2)
Total reclassifications for the period	$ (2)	$ (1)	$ (1)	$ 2	$ (4)

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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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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