RESULTS FOR THE YEAR (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Analysis of income and expense [abstract]
Percent of increase in operating profit	1.10%	(2.00%)

Increase (Decrease) In Profit (Loss) In Operating Activities, Percent

No definition available.

Name:	nvo_IncreaseDecreaseInProfitLossInOperatingActivitiesPercent
Namespace Prefix:	nvo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration