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SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Detail) - Allowance for doubtful accounts receivable - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Balance at beginning of period | $ 5,485 | $ 5,095 | $ 5,339
Charged to costs and expenses | 1,043 | 1,609 | 1,103
Charged to other accounts | 906 | 0 | 0
Other | (1,088) | (1,163) | (1,139)
Balance at end of period | 6,803 | 5,485 | 5,095
Foreign Currency Translation |  |  |
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] |  |  |
Cumulative translation adjustment | $ 457 | $ (56) | $ (208)

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- Definition Amount of increase (decrease) in valuation and qualifying accounts and reserves from adjustment. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
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