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Percentage of employees' gross pay for which the employer contributes in addition to the matching contribution to a defined contribution plan.

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Represents Railroad Retirement System Agreement.

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Represents the weighted-average maturity of the Pension Plan debt portfolio.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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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 net periodic benefit cost (credit) for defined benefit plan.

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Amount of cost for defined contribution plan.

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Amount of contributions made by entity participating in defined benefit plan, defined as multiple-employer plan but accounted for as multiemployer plan.

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