Pension Plans and Postretirement Benefits - Additional Information (Details) - Pension benefits - USD ($)	12 Months Ended
Dec. 31, 2018	Sep. 30, 2019
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer minimum contribution requirements		$ 0
Anticipated employer cash contributions		0
Cash contributions	$ 0
Canada
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Anticipated employer cash contributions		$ 300,000
Cash contributions	$ 700,000

Defined Benefit Plans, Employer Minimum Contribution Requirements

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

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