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v3.20.1

LEASES - Narrative (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2020 USD ($) ft² service_station branch | Mar. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items] |  |
Cash paid for amounts included in the measurement of operating leases liabilities | $ | $ 479 | $ 511
Hong Kong |  |
Lessee, Lease, Description [Line Items] |  |
Leased area (sq ft) | 9,600 |
Rolling Hills Estates, California |  |
Lessee, Lease, Description [Line Items] |  |
Leased area (sq ft) | 4,900 |
Monterey Park, California |  |
Lessee, Lease, Description [Line Items] |  |
Leased area (sq ft) | 2,400 |
Richmond, British Columbia |  |
Lessee, Lease, Description [Line Items] |  |
Leased area (sq ft) | 1,600 |
Metuchen, New Jersey |  |
Lessee, Lease, Description [Line Items] |  |
Leased area (sq ft) | 2,000 |
China |  |
Lessee, Lease, Description [Line Items] |  |
Number of leased branches | branch | 9 |
Number of leased service stations | service_station | 11 |

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- Definition Lessee, Leased Area + References No definition available. + Details
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Namespace Prefix: | nhtc_
Data Type: | num:areaItemType
Balance Type: | na
Period Type: | instant

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- Definition Lessee, Number of Branches + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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- Definition Lessee, Number of Service Stations + References No definition available. + Details
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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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- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
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- Details
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- Details
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