Condensed Consolidating Financial Information of Guarantor Subsidiaries CONDENSED CONSOLIDATING BALANCE SHEETS (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Sep. 30, 2013	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
ASSETS
Cash and cash equivalents	$ 175			$ 106		$ 36		$ 203
Accounts receivable, net	804			793
Intercompany receivable (payable)	0			0
Inventory	70			68
Prepaid expenses and other assets	53			111
Deferred taxes	260			265
Total current assets	1,362			1,343
Rental equipment, net	5,374			4,966
Property and equipment, net	421			428
Investments in subsidiaries	0			0
Goodwill, net	2,953	[1]	2,300	2,970	[1]	289	[1]	198	[1]
Other intangible assets, net	1,018			1,200
Other long-term assets	103			119
Total assets	11,231			11,026
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	604			630
Accounts payable	292			286
Accrued expenses and other liabilities	390			435
Total current liabilities	1,286			1,351
Long-term debt	6,569			6,679
Subordinated convertible debentures	0			55
Deferred taxes	1,459			1,302
Other long-term liabilities	69			65
Total liabilities	9,383			9,452
Temporary equity (note 12)	20			31
Total stockholders’ equity (deficit)	1,828			1,543
Total liabilities and stockholders’ equity	11,231			11,026
Parent [Member]
ASSETS
Cash and cash equivalents	0			0		0		0
Accounts receivable, net	0			0
Intercompany receivable (payable)	308			168
Inventory	0			0
Prepaid expenses and other assets	0			0
Deferred taxes	0			0
Total current assets	308			168
Rental equipment, net	0			0
Property and equipment, net	48			41
Investments in subsidiaries	1,648			1,575
Goodwill, net	0			0
Other intangible assets, net	0			0
Other long-term assets	2			4
Total assets	2,006			1,788
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	136			137
Accounts payable	0			0
Accrued expenses and other liabilities	1			1
Total current liabilities	137			138
Long-term debt	0			0
Subordinated convertible debentures	0			55
Deferred taxes	21			21
Other long-term liabilities	0			0
Total liabilities	158			214
Temporary equity (note 12)	20			31
Total stockholders’ equity (deficit)	1,828			1,543
Total liabilities and stockholders’ equity	2,006			1,788
URNA [Member]
Condensed Financial Information Other Details [Abstract]
Ownership percentage in subsidiaries	100.00%
ASSETS
Cash and cash equivalents	17			20		6		4
Accounts receivable, net	36			43
Intercompany receivable (payable)	(257)			(108)
Inventory	62			60
Prepaid expenses and other assets	42			87
Deferred taxes	258			263
Total current assets	158			365
Rental equipment, net	4,768			4,357
Property and equipment, net	313			333
Investments in subsidiaries	1,132			1,029
Goodwill, net	2,708			2,710
Other intangible assets, net	931			1,094
Other long-term assets	100			115
Total assets	10,110			10,003
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	38			40
Accounts payable	254			243
Accrued expenses and other liabilities	327			361
Total current liabilities	619			644
Long-term debt	6,421			6,522
Subordinated convertible debentures	0			0
Deferred taxes	1,357			1,199
Other long-term liabilities	65			63
Total liabilities	8,462			8,428
Temporary equity (note 12)	0			0
Total stockholders’ equity (deficit)	1,648			1,575
Total liabilities and stockholders’ equity	10,110			10,003
Guarantor Subsidiaries [Member]
Condensed Financial Information Other Details [Abstract]
Ownership percentage in subsidiaries	100.00%
ASSETS
Cash and cash equivalents	0			0		0		0
Accounts receivable, net	0			0
Intercompany receivable (payable)	(51)			(49)
Inventory	0			0
Prepaid expenses and other assets	1			10
Deferred taxes	0			0
Total current assets	(50)			(39)
Rental equipment, net	0			0
Property and equipment, net	20			16
Investments in subsidiaries	997			932
Goodwill, net	0			0
Other intangible assets, net	0			0
Other long-term assets	0			0
Total assets	967			909
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	0			0
Accounts payable	0			0
Accrued expenses and other liabilities	25			33
Total current liabilities	25			33
Long-term debt	140			150
Subordinated convertible debentures	0			0
Deferred taxes	0			0
Other long-term liabilities	0			0
Total liabilities	165			183
Temporary equity (note 12)	0			0
Total stockholders’ equity (deficit)	802			726
Total liabilities and stockholders’ equity	967			909
Non Guarantor Subsidiaries Foreign [Member]
ASSETS
Cash and cash equivalents	158			86		30		199
Accounts receivable, net	140			146
Intercompany receivable (payable)	(132)			(163)
Inventory	8			8
Prepaid expenses and other assets	10			14
Deferred taxes	2			2
Total current assets	186			93
Rental equipment, net	606			609
Property and equipment, net	40			38
Investments in subsidiaries	0			0
Goodwill, net	245			260
Other intangible assets, net	87			106
Other long-term assets	0			0
Total assets	1,164			1,106
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	0			0
Accounts payable	38			43
Accrued expenses and other liabilities	36			40
Total current liabilities	74			83
Long-term debt	8			7
Subordinated convertible debentures	0			0
Deferred taxes	81			82
Other long-term liabilities	4			2
Total liabilities	167			174
Temporary equity (note 12)	0			0
Total stockholders’ equity (deficit)	997			932
Total liabilities and stockholders’ equity	1,164			1,106
Non Guarantor Subsidiaries SPV [Member]
ASSETS
Cash and cash equivalents	0			0		0		0
Accounts receivable, net	628			604
Intercompany receivable (payable)	0			0
Inventory	0			0
Prepaid expenses and other assets	0			0
Deferred taxes	0			0
Total current assets	628			604
Rental equipment, net	0			0
Property and equipment, net	0			0
Investments in subsidiaries	0			0
Goodwill, net	0			0
Other intangible assets, net	0			0
Other long-term assets	1			0
Total assets	629			604
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	430			453
Accounts payable	0			0
Accrued expenses and other liabilities	1			0
Total current liabilities	431			453
Long-term debt	0			0
Subordinated convertible debentures	0			0
Deferred taxes	0			0
Other long-term liabilities	0			0
Total liabilities	431			453
Temporary equity (note 12)	0			0
Total stockholders’ equity (deficit)	198			151
Total liabilities and stockholders’ equity	629			604
Eliminations [Member]
ASSETS
Cash and cash equivalents	0			0		0		0
Accounts receivable, net	0			0
Intercompany receivable (payable)	132			152
Inventory	0			0
Prepaid expenses and other assets	0			0
Deferred taxes	0			0
Total current assets	132			152
Rental equipment, net	0			0
Property and equipment, net	0			0
Investments in subsidiaries	(3,777)			(3,536)
Goodwill, net	0			0
Other intangible assets, net	0			0
Other long-term assets	0			0
Total assets	(3,645)			(3,384)
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	0			0
Accounts payable	0			0
Accrued expenses and other liabilities	0			0
Total current liabilities	0			0
Long-term debt	0			0
Subordinated convertible debentures	0			0
Deferred taxes	0			0
Other long-term liabilities	0			0
Total liabilities	0			0
Temporary equity (note 12)	0			0
Total stockholders’ equity (deficit)	(3,645)			(3,384)
Total liabilities and stockholders’ equity	(3,645)			(3,384)
ABL Facility, Accounts Receivable Securitization Facility, and Other Agreements [Member] | URNA [Member]
Condensed Financial Information Other Details [Abstract]
Line of credit facility, restricted payment capacity	$ 466

[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.