Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands		1 Months Ended	6 Months Ended
	Jul. 27, 2016	Mar. 31, 2015	Jun. 30, 2016
Commitments and Contingent Liabilities
Lease period, minimum			5 years
Lease period, maximum			20 years
Loss Contingencies
Letters of credit outstanding			$ 32,800
Surety bonds posted			12,700
Subsequent event
Loss Contingencies
Ownership interest in Penske Truck Leasing Co (as a percent)	23.40%
Holdings | Holdings Bond
Loss Contingencies
Senior unsecured notes issued			$ 700,000
Senior subordinated convertible notes, interest rate (as a percent)			3.80%
Percentage of interest and principal due to the co-obligor as a result of the change in ownership and subsequent relief of debt obligation		50.10%
Percentage of expenses relating to the debt obligation due to the co-obligor as a result of the change in ownership and subsequent relief of debt obligation		100.00%
Penske Truck Leasing Co., L.P. | Subsequent event
Loss Contingencies
Ownership interest in Penske Truck Leasing Co (as a percent)	23.40%
Mitsui and Co
Loss Contingencies
Purchase of ownership interest		20.00%
Mitsui and Co | Subsequent event
Loss Contingencies
Ownership interest in Penske Truck Leasing Co (as a percent)	20.00%
Penske Corporation | Subsequent event
Loss Contingencies
Ownership interest in Penske Truck Leasing Co (as a percent)	41.10%
Guarantee of Indebtedness of Others | GEC
Loss Contingencies
Percentage of interest agreed to indemnify if GEC required to make any payments of principal or interest			9.00%
Annual fee pay for acting as co-obligor			$ 950
Value of principal repayment included in maximum amount of Company's potential obligations			$ 63,100