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.

No definition available.

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- Definition

The number of share options outstanding in a share-based payment arrangement.

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- Definition

The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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- Definition

The weighted average remaining contractual life of outstanding share options. [Refer: Weighted average [member]]

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Share-based payments - Summary of options outstanding (Details) Option in Millions	12 Months Ended
	Mar. 31, 2021 Option £ / shares	Mar. 31, 2020 Option £ / shares	Mar. 31, 2019 Option £ / shares	Mar. 31, 2018 Option £ / shares
Summary of options outstanding and exercisable
Outstanding shares \| Option	62	53	46	40
Weighted average exercise price	£ 1.07	£ 1.19	£ 1.40	£ 1.64
Weighted average remaining contractual life	30 months	30 months
Minimum
Summary of options outstanding and exercisable
Weighted average exercise price	£ 0.98
Maximum
Summary of options outstanding and exercisable
Weighted average exercise price	£ 1.89