Operating assets and liabilities - Retirement benefit obligations - Sensitivity Analysis (Details) - DKK (kr) kr in Millions	Dec. 31, 2019	Dec. 31, 2018
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Discount rate		2.10%
1 %-point increase		kr (369)
1 %-point decrease		kr 458
Discount rate (decrease)/increase
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Discount rate	1.30%
Percentage of reasonably possible increase in actuarial assumption	1.00%
Percentage of reasonably possible decrease in actuarial assumption	1.00%
1 %-point increase	kr (366)
1 %-point decrease	kr 465
Future remuneration growth (decrease)/increase
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Future remuneration	2.40%	2.50%
Percentage of reasonably possible increase in actuarial assumption	1.00%
Percentage of reasonably possible decrease in actuarial assumption	1.00%
1 %-point increase	kr 105	kr 99
1 %-point decrease	kr (94)	kr (89)

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-URIDate 2019-03-27

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- Definition

The expected rate of salary increases used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by a decrease in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2019-01-01
-Paragraph 145
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-URIDate 2019-03-27

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The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

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The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

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The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

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