Taxation - Tax Charge (Detail) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Corporation tax
Current year	£ 423.0	£ 404.2	£ 383.0
Prior years	(63.4)	(108.1)	(97.2)
Corporation tax	359.6	296.1	285.8
Deferred tax
Current year	(78.3)	(41.5)	(207.4)
Prior years	(6.3)	1.4	4.6
Deferred tax	(84.6)	(40.1)	(202.8)
Tax charge	£ 275.0	£ 256.0	£ 83.0

Adjustments of tax expense (income) recognised in the period for current tax of prior periods.

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Adjustments of tax expense (income) recognised in the period for the deferred tax of prior periods.

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The amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period.

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The amount of current tax expense (income) and adjustments for the current tax of prior periods. [Refer: Current tax expense (income); Adjustments for current tax of prior periods]

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The amount of tax expense (income) relating to changes in deferred tax liabilities and deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

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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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