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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Contribution Plan [Member] | 401(k) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined contribution expense | $ 3.8 | $ 4.1 | $ 3.5

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration

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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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Namespace Prefix: | us-gaap_
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Period Type: | duration

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |