Other Balance Sheet Information - Other Non-Current Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other non-current liabilities:
Asset retirement obligations	$ 9,018	$ 8,931
Environmental liabilities	2,227	1,977
Accrued sales, use and other taxes	17,024	17,142
Other	67	116
Total	$ 28,336	$ 28,166

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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