Statement Of Changes In Equity [Abstract]

Direct Line Insurance Group PLC - Filing #3490597

Concept	As at 2021-12-31	As at 2021-12-31	As at 2021-12-31	2021-01-01 to 2021-12-31	2021-01-01 to 2021-12-31	As at 2021-12-31	As at 2021-12-31	2021-01-01 to 2021-12-31	2021-01-01 to 2021-12-31	As at 2021-12-31	2021-01-01 to 2021-12-31	2021-01-01 to 2021-12-31	As at 2021-12-31	2021-01-01 to 2021-12-31	As at 2021-12-31	As at 2021-12-31	2021-01-01 to 2021-12-31	2021-01-01 to 2021-12-31	2020-01-01 to 2020-12-31	2020-01-01 to 2020-12-31	2020-01-01 to 2020-12-31	As at 2020-12-31	2020-01-01 to 2020-12-31	2020-01-01 to 2020-12-31	As at 2020-12-31	As at 2020-12-31	2020-01-01 to 2020-12-31	As at 2020-12-31	As at 2020-12-31	As at 2020-12-31	As at 2020-12-31	As at 2020-12-31	2020-01-01 to 2020-12-31	2020-01-01 to 2020-12-31	As at 2020-12-31	2020-01-01 to 2020-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31	As at 2019-12-31
Statement of changes in equity [abstract]
Statement of changes in equity [line items]
Equity	41,400,000 GBP	1,454,800,000 GBP	982,900,000 GBP	—	—	2,896,700,000 GBP	346,500,000 GBP	—	—	9,000,000 GBP	—	—	2,550,200,000 GBP	—	300,000 GBP	145,200,000 GBP	—	—	—	—	—	1,056,100,000 GBP	—	—	148,900,000 GBP	2,699,700,000 GBP	—	83,900,000 GBP	346,500,000 GBP	40,300,000 GBP	— GBP	3,046,200,000 GBP	—	—	1,451,100,000 GBP	—	346,500,000 GBP	2,643,600,000 GBP	47,500,000 GBP	100,000 GBP	1,450,000,000 GBP	2,990,100,000 GBP	1,026,200,000 GBP	30,200,000 GBP	150,000,000 GBP
Changes in equity [abstract]
Comprehensive income [abstract]
Profit (loss)	—	—	—	— GBP	343,700,000 GBP	—	—	— GBP	— GBP	—	— GBP	— GBP	—	— GBP	—	—	343,700,000 GBP	343,700,000 GBP	— GBP	— GBP	367,200,000 GBP	—	— GBP	— GBP	—	—	367,200,000 GBP	—	—	—	—	—	— GBP	— GBP	—	367,200,000 GBP	—	—	—	—	—	—	—	—	—
Other comprehensive income	—	—	—	— GBP	72,200,000 GBP	—	—	— GBP	74,900,000 GBP	—	300,000 GBP	— GBP	—	— GBP	—	—	72,200,000 GBP	3,000,000 GBP	— GBP	36,400,000 GBP	36,200,000 GBP	—	— GBP	— GBP	—	—	100,000 GBP	—	—	—	—	—	— GBP	100,000 GBP	—	36,200,000 GBP	—	—	—	—	—	—	—	—	—
Comprehensive income	—	—	—	— GBP	271,500,000 GBP	—	—	— GBP	74,900,000 GBP	—	300,000 GBP	— GBP	—	— GBP	—	—	271,500,000 GBP	346,700,000 GBP	— GBP	36,400,000 GBP	403,400,000 GBP	—	— GBP	— GBP	—	—	367,100,000 GBP	—	—	—	—	—	— GBP	100,000 GBP	—	403,400,000 GBP	—	—	—	—	—	—	—	—	—
Dividends recognised as distributions to owners	—	—	—	— GBP	317,400,000 GBP	—	—	— GBP	— GBP	—	— GBP	— GBP	—	— GBP	—	—	317,400,000 GBP	317,400,000 GBP	— GBP	— GBP	312,500,000 GBP	—	— GBP	— GBP	—	—	312,500,000 GBP	—	—	—	—	—	— GBP	— GBP	—	312,500,000 GBP	—	—	—	—	—	—	—	—	—
Increase (decrease) through share-based payment transactions, equity	—	—	—	— GBP	17,000,000 GBP	—	—	— GBP	— GBP	—	— GBP	— GBP	—	— GBP	—	—	17,000,000 GBP	17,000,000 GBP	— GBP	— GBP	18,500,000 GBP	—	— GBP	— GBP	—	—	18,500,000 GBP	—	—	—	—	—	— GBP	— GBP	—	18,500,000 GBP	—	—	—	—	—	—	—	—	—