Capital Structure, Financial Risk and Related Items - Valuation Assumptions for Warrants Granted (Details) - DKK (kr) kr / shares in Units, kr in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Results of the year [Line Items]
Fair value per warrant on grant date	kr 664.08	kr 701.82	kr 631.51
Share price	2,244.22	2,282.35	2,009.79
Exercise price	kr 2,244.22	kr 2,282.35	kr 2,009.79
Expected dividend yield	0.00%	0.00%	0.00%
Expected stock price volatility	33.50%	36.60%	37.00%
Risk-free interest rate	0.15%	(0.54%)	(0.58%)
Expected life of warrants	5 years	5 years	5 years
Fair value of warrants granted	kr 172	kr 124	kr 75
Fair value of RSU granted (in dollars per share)	kr 2,250.18	kr 2,236.44	kr 1,927.83
Total tax expense (income)	kr 1,513	kr 975	kr 1,146
Current tax benefit recorded directly in shareholders' equity	22	31	44
RSU
Results of the year [Line Items]
Fair value of RSU granted	kr 612	kr 416	kr 90

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The weighted average exercise price of warrants granted.

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The percentage of an expected dividend used to calculate the fair value of warrants granted.

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The expected life of share options granted.

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The expected volatility of the share price used to calculate the fair value of warrants granted.

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The weighted average fair value per warrant on grant date.

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Weighted average risk free interest rate of warrants granted.

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The weighted average price used as input to the option pricing model to calculate the fair value of warrants granted.

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The weighted average fair value of other equity instruments (i.e. other than share options) granted in a share-based payment arrangement.

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The amount of current tax relating to particular items that are charged or credited directly to equity, for example: (a) an adjustment to the opening balance of retained earnings resulting from either a change in accounting policy that is applied retrospectively or the correction of an error; and (b) amounts arising on initial recognition of the equity component of a compound financial instrument. [Refer: Retained earnings; Financial instruments, class [member]]

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The weighted average fair value at the measurement date of granted equity instruments other than share options. [Refer: Weighted average [member]]

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