Condensed Consolidating Financial Information of Guarantor Subsidiaries - CONDENSED CONSOLIDATING BALANCE SHEETS (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Cash and cash equivalents	$ 52	$ 43
Accounts receivable, net	1,530	1,545
Intercompany receivable (payable)	0	0
Inventory	120	109
Prepaid expenses and other assets	140	64
Total current assets	1,842	1,761
Property and equipment, net	604	614
Investments in subsidiaries	0	0
Goodwill	5,154	5,058	$ 4,082	$ 3,260
Other intangible assets, net	895	1,084
Operating lease right-of-use assets	669
Other long-term assets	19	16
Total assets	18,970	18,133	$ 15,030
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt	997	903
Accounts payable	454	536
Accrued expenses and other liabilities	747	677
Total current liabilities	2,198	2,116
Long-term debt	10,431	10,844
Deferred taxes	1,887	1,687
Operating lease liabilities	533
Other long-term liabilities	91	83
Total liabilities	15,140	14,730
Total stockholders’ equity (deficit)	3,830	3,403
Total liabilities and stockholders’ equity	18,970	18,133
Eliminations
ASSETS
Cash and cash equivalents	0	0
Accounts receivable, net	0	0
Intercompany receivable (payable)	0	0
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	0	0
Investments in subsidiaries	(4,214)	(4,452)
Goodwill	0	0
Other intangible assets, net	0	0
Operating lease right-of-use assets	0
Other long-term assets	0	0
Total assets	(4,214)	(4,452)
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
Operating lease liabilities	0
Other long-term liabilities	0	0
Total liabilities	0	0
Total stockholders’ equity (deficit)	(4,214)	(4,452)
Total liabilities and stockholders’ equity	(4,214)	(4,452)
Parent | Reportable Legal Entities
ASSETS
Cash and cash equivalents	0	0
Accounts receivable, net	0	0
Intercompany receivable (payable)	2,255	1,534
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	2,255	1,534
Investments in subsidiaries	1,509	1,826
Goodwill	0	0
Other intangible assets, net	0	0
Operating lease right-of-use assets	0
Other long-term assets	12	9
Total assets	3,852	3,426
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt	0	1
Accounts payable	0	0
Accrued expenses and other liabilities	0	0
Total current liabilities	0	1
Long-term debt	0	0
Deferred taxes	22	22
Operating lease liabilities	0
Other long-term liabilities	0	0
Total liabilities	22	23
Total stockholders’ equity (deficit)	3,830	3,403
Total liabilities and stockholders’ equity	3,852	3,426
URNA | Reportable Legal Entities
ASSETS
Cash and cash equivalents	28	1
Accounts receivable, net	0	0
Intercompany receivable (payable)	(2,130)	(1,423)
Inventory	108	96
Prepaid expenses and other assets	124	60
Total current assets	(1,870)	(1,266)
Investments in subsidiaries	1,636	1,646
Goodwill	4,759	4,661
Other intangible assets, net	833	1,004
Operating lease right-of-use assets	194
Other long-term assets	7	7
Total assets	14,954	15,424
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt	66	50
Accounts payable	395	481
Accrued expenses and other liabilities	572	619
Total current liabilities	1,033	1,150
Long-term debt	10,402	10,778
Deferred taxes	1,768	1,587
Operating lease liabilities	151
Other long-term liabilities	91	83
Total liabilities	13,445	13,598
Total stockholders’ equity (deficit)	1,509	1,826
Total liabilities and stockholders’ equity	14,954	15,424
Guarantor Subsidiaries | Reportable Legal Entities
ASSETS
Cash and cash equivalents	0	0
Accounts receivable, net	0	0
Intercompany receivable (payable)	(112)	(96)
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	(112)	(96)
Investments in subsidiaries	1,069	980
Goodwill	0	0
Other intangible assets, net	0	0
Operating lease right-of-use assets	403
Other long-term assets	0	0
Total assets	1,438	924
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	118	14
Total current liabilities	118	14
Long-term debt	7	9
Deferred taxes	0	0
Operating lease liabilities	323
Other long-term liabilities	0	0
Total liabilities	448	23
Total stockholders’ equity (deficit)	990	901
Total liabilities and stockholders’ equity	1,438	924
Foreign | Reportable Legal Entities
ASSETS
Cash and cash equivalents	24	42
Accounts receivable, net	171	159
Intercompany receivable (payable)	(14)	(15)
Inventory	12	13
Prepaid expenses and other assets	16	4
Total current assets	209	203
Investments in subsidiaries	0	0
Goodwill	395	397
Other intangible assets, net	62	80
Operating lease right-of-use assets	72
Other long-term assets	0	0
Total assets	1,580	1,425
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt	2	2
Accounts payable	59	55
Accrued expenses and other liabilities	55	42
Total current liabilities	116	99
Long-term debt	22	57
Deferred taxes	97	78
Operating lease liabilities	59
Other long-term liabilities	0	0
Total liabilities	294	234
Total stockholders’ equity (deficit)	1,286	1,191
Total liabilities and stockholders’ equity	1,580	1,425
SPV | Reportable Legal Entities
ASSETS
Cash and cash equivalents	0	0
Accounts receivable, net	1,359	1,386
Intercompany receivable (payable)	1	0
Inventory	0	0
Prepaid expenses and other assets	0	0
Total current assets	1,360	1,386
Investments in subsidiaries	0	0
Goodwill	0	0
Other intangible assets, net	0	0
Operating lease right-of-use assets	0
Other long-term assets	0	0
Total assets	1,360	1,386
LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)
Short-term debt and current maturities of long-term debt	929	850
Accounts payable	0	0
Accrued expenses and other liabilities	2	2
Total current liabilities	931	852
Long-term debt	0	0
Deferred taxes	0	0
Operating lease liabilities	0
Other long-term liabilities	0	0
Total liabilities	931	852
Total stockholders’ equity (deficit)	429	534
Total liabilities and stockholders’ equity	1,360	1,386
Rental equipment, net
ASSETS
Property and equipment, net	9,787	9,600
Rental equipment, net | Eliminations
ASSETS
Property and equipment, net	0	0
Rental equipment, net | Parent | Reportable Legal Entities
ASSETS
Property and equipment, net	0	0
Rental equipment, net | URNA | Reportable Legal Entities
ASSETS
Property and equipment, net	8,995	8,910
Rental equipment, net | Guarantor Subsidiaries | Reportable Legal Entities
ASSETS
Property and equipment, net	0	0
Rental equipment, net | Foreign | Reportable Legal Entities
ASSETS
Property and equipment, net	792	690
Rental equipment, net | SPV | Reportable Legal Entities
ASSETS
Property and equipment, net	0	0
Property and equipment, net
ASSETS
Property and equipment, net	604	614
Property and equipment, net | Eliminations
ASSETS
Property and equipment, net	0	0
Property and equipment, net | Parent | Reportable Legal Entities
ASSETS
Property and equipment, net	76	57
Property and equipment, net | URNA | Reportable Legal Entities
ASSETS
Property and equipment, net	400	462
Property and equipment, net | Guarantor Subsidiaries | Reportable Legal Entities
ASSETS
Property and equipment, net	78	40
Property and equipment, net | Foreign | Reportable Legal Entities
ASSETS
Property and equipment, net	50	55
Property and equipment, net | SPV | Reportable Legal Entities
ASSETS
Property and equipment, net	$ 0	$ 0