Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 reporting_unit		Dec. 31, 2012		Dec. 31, 2011		Sep. 30, 2013	Dec. 31, 2010
Significant Accounting Policies [Line Items]
Percentage of fair value in excess of carrying amount	15.00%
Number of reporting units evaluated for impairment	10
Goodwill, net	$ 2,953,000,000	[1]	$ 2,970,000,000	[1]	$ 289,000,000	[1]	$ 2,300,000,000	$ 198,000,000	[1]
Number of reporting units impacted by internal reporting changes evaluated for impairment	4
Goodwill, impairment testing, change in reporting structure, amount							626,000,000
Impairment, percent of fair value exceeding carrying value	44.00%
Deferred revenue	30,000,000		26,000,000
Advertising expense	0		0		0
Insurance stop loss limit, self insured events	600,000
Percent threshold used to define more likely than not for tax purposes (greater than 50%)	50.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration risk, percentage	1.00%		2.00%
General Liability [Member]
Significant Accounting Policies [Line Items]
Insurance deductible, per occurrence	2,000,000		2,000,000
Workers Compensation [Member]
Significant Accounting Policies [Line Items]
Insurance deductible, per occurrence	1,000,000		1,000,000
Automobile Liability [Member]
Significant Accounting Policies [Line Items]
Insurance deductible, per occurrence	2,000,000		2,000,000
Trade Names and Trademarks [Member]
Significant Accounting Policies [Line Items]
Finite lived intangible assets life	5 years
Assets Leased to Others [Member]
Significant Accounting Policies [Line Items]
PP&E additions	44,000,000		24,000,000		10,000,000
Cost of services, maintenance costs	$ 563,000,000		$ 455,000,000		$ 291,000,000
Minimum [Member] | Customer Relationships [Member]
Significant Accounting Policies [Line Items]
Finite lived intangible assets life	8 years
Minimum [Member] | Assets Leased to Others [Member]
Significant Accounting Policies [Line Items]
PP&E useful life	2 years
PP&E salvage value	0.00%
Minimum [Member] | Other Capitalized Property Plant and Equipment [Member]
Significant Accounting Policies [Line Items]
PP&E useful life	2 years
Maximum [Member] | Revenue [Member] | Customer Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration risk, percentage	1.00%		1.00%		1.00%
Maximum [Member] | Non-Compete Agreements [Member]
Significant Accounting Policies [Line Items]
Finite lived intangible assets life	5 years
Maximum [Member] | Customer Relationships [Member]
Significant Accounting Policies [Line Items]
Finite lived intangible assets life	15 years
Maximum [Member] | Assets Leased to Others [Member]
Significant Accounting Policies [Line Items]
PP&E useful life	12 years
PP&E salvage value	10.00%
Maximum [Member] | Other Capitalized Property Plant and Equipment [Member]
Significant Accounting Policies [Line Items]
PP&E useful life	39 years

[1] The total carrying amount of goodwill for all periods in the table above is reflected net of $1,557 of accumulated impairment charges, which were primarily recorded in our general rentals segment.