XML 101 R84.htm IDEA: XBRL DOCUMENT
v3.20.1

Quarterly Results of Operations - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes | $ 6,300 | $ (1,600) | $ 5,900 | $ 15,200 | $ 2,800 | $ (15,400) | $ (42,600) | $ 14,200 | $ 25,844 | $ (41,017) | $ 116,100
Litigation Settlement Expense |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes |  |  | (15,200) |  |  |  | $ (49,000) |  |  |  |
GILTI | Kronos |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes |  |  |  |  | $ (900) |  |  |  |  |  |
Gain From a Sale of Excess Property |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes |  | 3,500 |  |  |  |  |  |  |  |  |
Gain From the Sale of Insurance And Risk Management |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes | 2,400 |  |  |  |  |  |  |  |  |  |
Insurance Recoveries |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes |  | $ 200 | $ 3,700 | $ 200 |  |  |  |  | $ 4,100 |  |
Decrease In German Trade Tax Rate | Kronos |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes | (1,300) |  |  |  |  |  |  |  |  |  |
Favorable Settlement Of Prior Year Tax Matter | Kronos |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes | 700 |  |  |  |  |  |  |  |  |  |
Insurance Settlement Gains | Kronos |  |  |  |  |  |  |  |  |  |  |
Effect Of Fourth Quarter Events [Line Items] |  |  |  |  |  |  |  |  |  |  |
Income (loss), net of income taxes | $ 500 |  |  |  |  |  |  |  |  |  |

X
- 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
Name: | us-gaap_EffectOfFourthQuarterEventsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669619-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669625-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=116637232&loc=SL114874131-224263 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_LitigationSettlementExpenseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_GlobalIntangibleLowTaxIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=nl_KronosWorldwideIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_GainFromSaleOfExcessPropertyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_GainFromSaleOfInsuranceAndRiskManagementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_InsuranceRecoveriesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_DecreaseInGermanTradeTaxRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_FavorableSettlementOfPriorYearTaxMatterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=nl_InsuranceSettlementGainsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |