Capital structure and financial items - Cash and cash equivalents, financial resources and free cash flow - Free cash flow (Details) - DKK (kr) kr in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Capital, Reserves And Other Equity Interest And Financial Instruments [Abstract]
Net cash generated from operating activities	kr 51,951	kr 46,782	kr 44,616
Net cash used in investing activities	(22,436)	(11,509)	(12,080)
Repayment on lease liabilities	(950)	(822)	0
Free cash flow	kr 28,565	kr 34,451	kr 32,536

The cash flows from (used in) investing activities, which are the acquisition and disposal of long-term assets and other investments not included in cash equivalents.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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The cash flows from (used in) operating activities, which are the principal revenue-producing activities of the entity and other activities that are not investing or financing activities. [Refer: Revenue]

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Free Cash Flow

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Repayment Of Lease Liabilities

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Share Capital, Reserves And Other Equity Interest And Financial Instruments [Abstract]

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