Financial Instruments Fair Value Risk - Additional Information (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of Detailed Information about Financial Instruments [Line Items]
Assets	€ 60,285	€ 56,429
De-recognised asset	36	43	€ 41
Proceed from disposal	45
Profit (loss) on disposal of investment	9
Unlisted investments include of investment	32	36
Level 3 [Member]
Disclosure of Detailed Information about Financial Instruments [Line Items]
Impact in income statement due to Level 3 instruments	26	94
Level 3 [Member] \| Unilever Ventures companies [Member]
Disclosure of Detailed Information about Financial Instruments [Line Items]
Unlisted investments include of investment	195	172
Level 3 [Member] \| Split-Dollar Life Insurance [Member] \| Fair value [Member]
Disclosure of Detailed Information about Financial Instruments [Line Items]
Assets	€ 22	€ 25

The amount of resources: (a) controlled by the entity as a result of past events; and (b) from which future economic benefits are expected to flow to the entity.

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