Segment Information about Reported Product Revenues, Depreciation and Amortization and Operating Income (Loss) (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Product revenues	$ 257,921	$ 264,586
Depreciation and amortization	11,052	12,892
Operating income (loss)	21,845	20,649
Industrial Segments
Segment Reporting Information [Line Items]
Product revenues	15,564	22,165
Industrial Segments \| CSZ-IC
Segment Reporting Information [Line Items]
Product revenues	3,418	10,213
Depreciation and amortization	0	625
Operating income (loss)	$ 198	$ 600

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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