Condensed Consolidating Financial Information of Guarantor Subsidiaries - CONDENSED CONSOLIDATING BALANCE SHEETS (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 179	$ 158	$ 175	$ 106
Accounts receivable, net	930	940
Intercompany receivable (payable)	0	0
Inventory	69	78
Prepaid expenses and other assets	116	122
Total current assets	1,294	1,298
Investments in subsidiaries	0	0
Goodwill	3,243	3,272	2,953	2,970
Other intangible assets, net	905	1,106
Other long-term assets	10	7
Total assets	12,083	12,129	10,876
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	607	618
Accounts payable	271	285
Accrued expenses and other liabilities	355	575
Total current liabilities	1,233	1,478
Long-term debt	7,555	7,344
Deferred taxes	1,765	1,444
Other long-term liabilities	54	65
Total liabilities	10,607	10,331
Temporary equity	0	2
Total stockholders’ equity (deficit)	1,476	1,796
Total liabilities and stockholders’ equity	12,083	12,129
Eliminations
ASSETS
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Intercompany receivable (payable)	101	121
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	101	121
Investments in subsidiaries	(3,189)	(3,555)
Goodwill	0	0
Other intangible assets, net	0	0
Other long-term assets	0	0
Total assets	(3,088)	(3,434)
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
Deferred taxes	0	0
Other long-term liabilities	0	0
Total liabilities	0	0
Temporary equity	0	0
Total stockholders’ equity (deficit)	(3,088)	(3,434)
Total liabilities and stockholders’ equity	(3,088)	(3,434)
Parent
ASSETS
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Intercompany receivable (payable)	144	476
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	144	476
Investments in subsidiaries	1,307	1,330
Goodwill	0	0
Other intangible assets, net	0	0
Other long-term assets	3	0
Total assets	1,499	1,849
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	1	32
Accounts payable	0	0
Accrued expenses and other liabilities	0	0
Total current liabilities	1	32
Long-term debt	4	0
Deferred taxes	18	19
Other long-term liabilities	0	0
Total liabilities	23	51
Temporary equity	0	2
Total stockholders’ equity (deficit)	1,476	1,796
Total liabilities and stockholders’ equity	$ 1,499	1,849
URNA
Condensed Financial Information Other Details [Abstract]
Ownership percentage in subsidiaries	100.00%
ASSETS
Cash and cash equivalents	$ 18	8	17	20
Accounts receivable, net	41	37
Intercompany receivable (payable)	40	(428)
Inventory	62	69
Prepaid expenses and other assets	98	113
Total current assets	259	(201)
Investments in subsidiaries	958	1,185
Goodwill	3,000	3,000
Other intangible assets, net	838	1,014
Other long-term assets	7	7
Total assets	11,053	10,735
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	34	38
Accounts payable	237	248
Accrued expenses and other liabilities	314	499
Total current liabilities	585	785
Long-term debt	7,430	7,208
Deferred taxes	1,677	1,348
Other long-term liabilities	54	64
Total liabilities	9,746	9,405
Temporary equity	0	0
Total stockholders’ equity (deficit)	1,307	1,330
Total liabilities and stockholders’ equity	$ 11,053	10,735
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)	(176)	(60)
Inventory	0	0
Prepaid expenses and other assets	0	1
Total current assets	(176)	(59)
Investments in subsidiaries	924	1,040
Goodwill	0	0
Other intangible assets, net	0	0
Other long-term assets	0	0
Total assets	768	1,002
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	14	19
Total current liabilities	14	19
Long-term debt	110	130
Deferred taxes	0	0
Other long-term liabilities	0	0
Total liabilities	124	149
Temporary equity	0	0
Total stockholders’ equity (deficit)	644	853
Total liabilities and stockholders’ equity	768	1,002
Non Guarantor Subsidiaries - Foreign
ASSETS
Cash and cash equivalents	161	150	158	86
Accounts receivable, net	104	144
Intercompany receivable (payable)	(109)	(109)
Inventory	7	9
Prepaid expenses and other assets	18	8
Total current assets	181	202
Investments in subsidiaries	0	0
Goodwill	243	272
Other intangible assets, net	67	92
Other long-term assets	0	0
Total assets	1,066	1,218
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	0	0
Accounts payable	34	37
Accrued expenses and other liabilities	27	57
Total current liabilities	61	94
Long-term debt	11	6
Deferred taxes	70	77
Other long-term liabilities	0	1
Total liabilities	142	178
Temporary equity	0	0
Total stockholders’ equity (deficit)	924	1,040
Total liabilities and stockholders’ equity	1,066	1,218
Non Guarantor Subsidiaries - SPV
ASSETS
Cash and cash equivalents	0	0	$ 0	$ 0
Accounts receivable, net	785	759
Intercompany receivable (payable)	0	0
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	785	759
Investments in subsidiaries	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Other long-term assets	0	0
Total assets	785	759
LIABILITIES AND STOCKHOLDERS’ EQUITY
Short-term debt and current maturities of long-term debt	572	548
Accounts payable	0	0
Accrued expenses and other liabilities	0	0
Total current liabilities	572	548
Long-term debt	0	0
Deferred taxes	0	0
Other long-term liabilities	0	0
Total liabilities	572	548
Temporary equity	0	0
Total stockholders’ equity (deficit)	213	211
Total liabilities and stockholders’ equity	$ 785	$ 759
8 1/4 percent Senior Notes
Condensed Financial Information Other Details [Abstract]
Stated interest rate	8.25%	8.25%
ABL Facility, Accounts Receivable Securitization Facility, and Other Agreements
Condensed Financial Information Other Details [Abstract]
Line of credit facility, restricted payment capacity	$ 499
ABL Facility, Accounts Receivable Securitization Facility, and Other Agreements | URNA
Condensed Financial Information Other Details [Abstract]
Line of credit facility, restricted payment capacity	355
Rental equipment, net
ASSETS
Property, plant and equipment, net	6,186	$ 6,008
Rental equipment, net | Eliminations
ASSETS
Property, plant and equipment, net	0	0
Rental equipment, net | Parent
ASSETS
Property, plant and equipment, net	0	0
Rental equipment, net | URNA
ASSETS
Property, plant and equipment, net	5,657	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	529	609
Rental equipment, net | Non Guarantor Subsidiaries - SPV
ASSETS
Property, plant and equipment, net	0	0
Property and equipment, net
ASSETS
Property, plant and equipment, net	445	438
Property and equipment, net | Eliminations
ASSETS
Property, plant and equipment, net	0	0
Property and equipment, net | Parent
ASSETS
Property, plant and equipment, net	45	43
Property and equipment, net | URNA
ASSETS
Property, plant and equipment, net	334	331
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	46	43
Property and equipment, net | Non Guarantor Subsidiaries - SPV
ASSETS
Property, plant and equipment, net	$ 0	$ 0