The interest rate used to adjust for the time value of money for the plan.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 715
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The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ References

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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 discretionary contributions made by an employer to a defined contribution plan.

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The increase (decrease) during the reporting period in the amount due to fund retirement benefits to employees, retired and disabled former employees.

+ References

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Pension and Other Postretirement Benefits - Narrative (Details) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2016	Jun. 30, 2017	Sep. 30, 2016	Mar. 31, 2017	Mar. 31, 2016	Aug. 31, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Reduction in long-term pension liabilities			$ 18,700,000
General Retirement Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discretionary contribution	$ 100,000,000
Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Curtailment charge			$ 500,000	$ 500,000	$ 0
Discount rate						3.57%
Pension Plans \| Forecast
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions		$ 0