Condensed Consolidating Financial Information of Guarantor Subsidiaries - CONDENSED CONSOLIDATING BALANCE SHEET (Details) - USD ($) $ in Millions		Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
ASSETS
Cash and cash equivalents		$ 171	$ 158	$ 168	$ 175
Accounts receivable, net		994	940
Intercompany receivable (payable)		0	0
Inventory		77	78
Prepaid expenses and other assets		58	122
Deferred taxes		126	248
Total current assets		1,426	1,546
Investments in subsidiaries		0	0
Goodwill		3,257	3,272
Other intangible assets, net		948	1,106
Other long-term assets		93	97
Total assets		12,598	12,467
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt	[1]	639	618
Accounts payable		475	285
Accrued expenses and other liabilities		403	575
Total current liabilities		1,517	1,478
Long-term debt		7,876	7,434
Deferred taxes		1,653	1,692
Other long-term liabilities		55	65
Total liabilities		11,101	10,669
Temporary equity		0	2
Total stockholders’ equity (deficit)		1,497	1,796
Total liabilities and stockholders’ equity		$ 12,598	12,467
Parent
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)		196	476
Inventory		0	0
Prepaid expenses and other assets		0	0
Deferred taxes		0	0
Total current assets		196	476
Investments in subsidiaries		1,288	1,330
Goodwill		0	0
Other intangible assets, net		0	0
Other long-term assets		0	1
Total assets		1,528	1,849
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt		9	32
Accounts payable		0	0
Accrued expenses and other liabilities		1	0
Total current liabilities		10	32
Long-term debt		3	0
Deferred taxes		18	19
Other long-term liabilities		0	0
Total liabilities		31	51
Temporary equity			2
Total stockholders’ equity (deficit)		1,497	1,796
Total liabilities and stockholders’ equity		1,528	1,849
URNA
ASSETS
Cash and cash equivalents		16	8	39	17
Accounts receivable, net		41	37
Intercompany receivable (payable)		22	(428)
Inventory		70	69
Prepaid expenses and other assets		48	113
Deferred taxes		125	246
Total current assets		322	45
Investments in subsidiaries		1,000	1,185
Goodwill		3,000	3,000
Other intangible assets, net		880	1,014
Other long-term assets		93	96
Total assets		11,494	11,071
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt		36	38
Accounts payable		428	248
Accrued expenses and other liabilities		366	499
Total current liabilities		830	785
Long-term debt		7,752	7,298
Deferred taxes		1,569	1,594
Other long-term liabilities		55	64
Total liabilities		10,206	9,741
Temporary equity			0
Total stockholders’ equity (deficit)		1,288	1,330
Total liabilities and stockholders’ equity		$ 11,494	11,071
Guarantor Subsidiaries
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)		(183)	(60)
Inventory		0	0
Prepaid expenses and other assets		1	1
Deferred taxes		0	0
Total current assets		(182)	(59)
Investments in subsidiaries		938	1,040
Goodwill		0	0
Other intangible assets, net		0	0
Other long-term assets		0	0
Total assets		776	1,002
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt		0	0
Accounts payable		0	0
Accrued expenses and other liabilities		14	19
Total current liabilities		14	19
Long-term debt		113	130
Deferred taxes		0	0
Other long-term liabilities		0	0
Total liabilities		127	149
Temporary equity			0
Total stockholders’ equity (deficit)		649	853
Total liabilities and stockholders’ equity		776	1,002
Non Guarantor Subsidiaries - Foreign
ASSETS
Cash and cash equivalents		155	150	129	158
Accounts receivable, net		116	144
Intercompany receivable (payable)		(143)	(109)
Inventory		7	9
Prepaid expenses and other assets		9	8
Deferred taxes		1	2
Total current assets		145	204
Investments in subsidiaries		0	0
Goodwill		257	272
Other intangible assets, net		68	92
Other long-term assets		0	0
Total assets		1,081	1,220
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt		0	0
Accounts payable		47	37
Accrued expenses and other liabilities		22	57
Total current liabilities		69	94
Long-term debt		8	6
Deferred taxes		66	79
Other long-term liabilities		0	1
Total liabilities		143	180
Temporary equity			0
Total stockholders’ equity (deficit)		938	1,040
Total liabilities and stockholders’ equity		1,081	1,220
Non Guarantor Subsidiaries - SPV
ASSETS
Cash and cash equivalents		0	0	0	0
Accounts receivable, net		837	759
Intercompany receivable (payable)		0	0
Inventory		0	0
Prepaid expenses and other assets		0	0
Deferred taxes		0	0
Total current assets		837	759
Investments in subsidiaries		0	0
Goodwill		0	0
Other intangible assets, net		0	0
Other long-term assets		0	0
Total assets		837	759
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt		594	548
Accounts payable		0	0
Accrued expenses and other liabilities		0	0
Total current liabilities		594	548
Long-term debt		0	0
Deferred taxes		0	0
Other long-term liabilities		0	0
Total liabilities		594	548
Temporary equity			0
Total stockholders’ equity (deficit)		243	211
Total liabilities and stockholders’ equity		$ 837	759
8 1/4 percent Senior Notes
Condensed Financial Information Other Details [Abstract]
Stated interest rate		8.25%
ABL Facility, Accounts Receivable Securitization Facility, and Other Agreements
Condensed Financial Information Other Details [Abstract]
Line of credit facility, restricted payment capacity		$ 494
ABL Facility, Accounts Receivable Securitization Facility, and Other Agreements | URNA
Condensed Financial Information Other Details [Abstract]
Line of credit facility, restricted payment capacity		298
Eliminations
ASSETS
Cash and cash equivalents		0	0	$ 0	$ 0
Accounts receivable, net		0	0
Intercompany receivable (payable)		108	121
Inventory		0	0
Prepaid expenses and other assets		0	0
Deferred taxes		0	0
Total current assets		108	121
Investments in subsidiaries		(3,226)	(3,555)
Goodwill		0	0
Other intangible assets, net		0	0
Other long-term assets		0	0
Total assets		(3,118)	(3,434)
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
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
Deferred taxes		0	0
Other long-term liabilities		0	0
Total liabilities		0	0
Temporary equity			0
Total stockholders’ equity (deficit)		(3,118)	(3,434)
Total liabilities and stockholders’ equity		(3,118)	(3,434)
Rental equipment, net
ASSETS
Property, plant and equipment, net		6,438	6,008
Rental equipment, net | Parent
ASSETS
Property, plant and equipment, net		0	0
Rental equipment, net | URNA
ASSETS
Property, plant and equipment, net		5,869	5,399
Rental equipment, net | Guarantor Subsidiaries
ASSETS
Property, plant and equipment, net		0	0
Rental equipment, net | Non Guarantor Subsidiaries - Foreign
ASSETS
Property, plant and equipment, net		569	609
Rental equipment, net | Non Guarantor Subsidiaries - SPV
ASSETS
Property, plant and equipment, net		0	0
Rental equipment, net | Eliminations
ASSETS
Property, plant and equipment, net		0	0
Property and equipment, net
ASSETS
Property, plant and equipment, net		436	438
Property and equipment, net | Parent
ASSETS
Property, plant and equipment, net		44	42
Property and equipment, net | URNA
ASSETS
Property, plant and equipment, net		330	332
Property and equipment, net | Guarantor Subsidiaries
ASSETS
Property, plant and equipment, net		20	21
Property and equipment, net | Non Guarantor Subsidiaries - Foreign
ASSETS
Property, plant and equipment, net		42	43
Property and equipment, net | Non Guarantor Subsidiaries - SPV
ASSETS
Property, plant and equipment, net		0	0
Property and equipment, net | Eliminations
ASSETS
Property, plant and equipment, net		$ 0	$ 0

[1] As of September 30, 2015, our short-term debt primarily reflects $594 of borrowings under our accounts receivable securitization facility.