The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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

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Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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

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Pensions and Other Postretirement Benefits - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Pension Benefit Plans
Employer Contributions
Company's contributions to its pension plans	$ 10.2	$ 10.2	$ 51.4
Pension Benefit Plans \| Minimum
Employer Contributions
Expected contributions	30.0
Pension Benefit Plans \| Maximum
Employer Contributions
Expected contributions	40.0
Postretirement Health Care Benefits
Employer Contributions
Benefit payments made	0.6	$ 0.2		$ 2.1
Expected benefit payments	$ 3.0