Restructuring Charges (Schedule of restructuring charges) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Restructuring Reserve [Roll Forward]
Beginning reserve balance	$ 20
Charged to Costs and Expenses	1	[1]	1
Payments and Other	(4)
Ending reserve balance	17
Branch closure charges
Restructuring Reserve [Roll Forward]
Beginning reserve balance	20
Charged to Costs and Expenses	1	[1]
Payments and Other	(4)
Ending reserve balance	17
Severance costs
Restructuring Reserve [Roll Forward]
Beginning reserve balance	0
Charged to Costs and Expenses	0	[1]
Payments and Other	0
Ending reserve balance	0
Closed Restructuring Program
Restructuring Reserve [Roll Forward]
Beginning reserve balance	9
Charged to Costs and Expenses	1	[1]
Payments and Other	(2)
Ending reserve balance	8
Closed Restructuring Program | Branch closure charges
Restructuring Reserve [Roll Forward]
Beginning reserve balance	9
Charged to Costs and Expenses	1	[1]
Payments and Other	(2)
Ending reserve balance	8
Closed Restructuring Program | Severance costs
Restructuring Reserve [Roll Forward]
Beginning reserve balance	0
Charged to Costs and Expenses	0	[1]
Payments and Other	0
Ending reserve balance	0
RSC Merger Related Restructuring Program
Restructuring Reserve [Roll Forward]
Beginning reserve balance	11
Charged to Costs and Expenses	0	[1]
Payments and Other	(2)
Ending reserve balance	9
RSC Merger Related Restructuring Program | Branch closure charges
Restructuring Reserve [Roll Forward]
Beginning reserve balance	11
Charged to Costs and Expenses	0	[1]
Payments and Other	(2)
Ending reserve balance	9
RSC Merger Related Restructuring Program | Severance costs
Restructuring Reserve [Roll Forward]
Beginning reserve balance	0
Charged to Costs and Expenses	0	[1]
Payments and Other	0
Ending reserve balance	$ 0

[1] Reflected in our condensed consolidated statements of income as “Restructuring charge.” These charges are not allocated to our reportable segments.