Pension and Other Postretirement Employee Benefit Plans - Additional Information (Detail 1) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		$ 0
Non-operating pension and other postretirment benefit (costs) income	[1]	1,279	$ (48)
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Employer contribution		100
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year		400
Non Qualified Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		11	(1,091)
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)		1,750	1,671
Employer contribution		0		$ 0
Cost of Sales [Member]
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax		300	400
Non-operating expense [Member]
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax			300
Selling, General and Administrative Expenses [Member]
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax		$ 200	$ (100)

[1] 2 As a result of the adoption of ASU 2017-07, certain pension and OPEB (costs) income have been reclassified from operating to non-operating income. The service cost component of pension and OPEB costs remains within segment operating income. Refer to Note 2, "Recently Adopted and New Accounting Standards," and Note 10, "Pension and Other Postretirement Benefit Plans," for additional detail.