U.K. Pension Plan Net Periodic Service Cost (Details) - Freightliner U.K. Pension Plan [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2016	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3,427
Interest cost	3,188
Expected return on plan assets	(4,074)
Net periodic benefit cost	2,541
Company's current year contribution	$ 3,000
Company contribution % required in shared cost arrangement	60.00%
Participant contribution % required in shared cost arrangement	40.00%
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Contributions in Current Fiscal Year		$ 9,700

Defined benefit plan, contribution percent by employer

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Defined benefit plan, contribution percent by participant

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Amount of contributions made by the employer to defined benefit plans.

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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 the employer's best estimate of contributions expected to be paid to the plan in the current fiscal period.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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