Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

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Pensions and Other Postretirement Benefits - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Pension Benefits
Employer Contributions
Company's contributions to its pension plans	$ 1.1	$ 2.0	$ 5.8
Pension Benefits \| Maximum
Employer Contributions
Expected contributions	10.0
Postretirement Health Care Benefits
Employer Contributions
Benefit payments	1.2	$ 1.3	$ 1.9
Expected benefit payments	$ 2.0