Restructuring Charges (Schedule of restructuring charges) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	$ 33
Charged to Costs and Expenses	2	$ 0
Payments and Other	(10)
Ending Reserve Balance	25
Branch closure charges
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	21
Charged to Costs and Expenses	0
Payments and Other	(4)
Ending Reserve Balance	17
Severance and other
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	12
Charged to Costs and Expenses	2
Payments and Other	(6)
Ending Reserve Balance	8
Closed Restructuring Programs
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	13
Charged to Costs and Expenses	0
Payments and Other	(2)
Ending Reserve Balance	11
Closed Restructuring Programs | Branch closure charges
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	13
Charged to Costs and Expenses	0
Payments and Other	(2)
Ending Reserve Balance	11
Closed Restructuring Programs | Severance and other
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	0
Charged to Costs and Expenses	0
Payments and Other	0
Ending Reserve Balance	0
NES/Neff/Project XL Restructuring Program
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	20
Charged to Costs and Expenses	2
Payments and Other	(8)
Ending Reserve Balance	14
NES/Neff/Project XL Restructuring Program | Branch closure charges
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	8
Charged to Costs and Expenses	0
Payments and Other	(2)
Ending Reserve Balance	6
NES/Neff/Project XL Restructuring Program | Severance and other
Restructuring Reserve [Roll Forward]
Beginning Reserve Balance	12
Charged to Costs and Expenses	2
Payments and Other	(6)
Ending Reserve Balance	$ 8