Segment Information (Percentage of Equipment Rental Revenue by Equipment Type) (Details) - Equipment rental revenue - Product concentration risk	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
General construction and industrial equipment | General rentals
Segment Reporting Information [Line Items]
Percentage of equipment rental revenue	43.00%	43.00%	43.00%
Aerial work platforms | General rentals
Segment Reporting Information [Line Items]
Percentage of equipment rental revenue	32.00%	32.00%	33.00%
General tools and light equipment | General rentals
Segment Reporting Information [Line Items]
Percentage of equipment rental revenue	8.00%	10.00%	10.00%
Power and HVAC equipment | Trench, power and pump
Segment Reporting Information [Line Items]
Percentage of equipment rental revenue	7.00%	6.00%	6.00%
Trench safety equipment | Trench, power and pump
Segment Reporting Information [Line Items]
Percentage of equipment rental revenue	6.00%	5.00%	5.00%
Pumps | Trench, power and pump
Segment Reporting Information [Line Items]
Percentage of equipment rental revenue	4.00%	4.00%	3.00%