Per the partnership agreement, the number of members on the advisory committee the Company is entitled to.

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Per the partnership agreement, the number of members on the advisory committee.

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Represents the partnership interest as a percent that my be transferred without complying with the right of first offer to remaining partners.

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The pro rata quarterly distribution rate.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Amount of dividend income on nonoperating securities.

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Related Party Transactions - Transactions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) individual	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
PTL
Related party transactions
Ownership interest in Penske Truck Leasing Co (as a percent)	28.90%
Penske Corporation \| PTL
Related party transactions
Ownership interest in Penske Truck Leasing Co (as a percent)	41.10%
Mitsui and Co \| PTL
Related party transactions
Ownership interest in Penske Truck Leasing Co (as a percent)	30.00%
Penske Corporation and its affiliates
Related party transactions
Provider's cost reimbursed	$ 6,700	$ 4,100	$ 5,400
Amount of Provider's cost received	38	30	80
Amount due from related party	27	20
Amount due to related party	$ 600	400
PTL
Related party transactions
Number of members on the advisory committee \| individual	6
Number of members on the advisory committee the Company is entitled to \| individual	1
Pro rata quarterly distribution rate (as a percent)	50.00%
Partnership interest that my be transferred without complying with the right of first offer (as a percent)	9.02%
Pro rata cash dividends received	$ 165,500	$ 72,200	$ 71,900
PTL \| Debt To Equity 3:1
Related party transactions
Pro rata quarterly distribution rate (as a percent)	80.00%