Pending Sale of the Specialty Fluids Business - Additional Information (Detail) - Sinomine (Hong Kong) Rare Metals Resources Co. Limited [Member] - Specialty Fluids [Member] - USD ($) $ in Millions	1 Months Ended
Jan. 31, 2019	Mar. 31, 2019
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Stock transaction value	$ 135
Purchase price	130
Additional cash royalties for lithium products	$ 5
Royalty payable term	10 years
Impairment charge		$ 20

Disposal group including discontinued operation impairment of assets held for sale.

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The amount of cash paid for royalties during the current period.

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