Taxation - Tax Charge (Detail) - GBP (£) £ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Corporation tax
Current year	£ 213.0	£ 172.7	£ 481.9
Prior years	(22.7)	(10.9)	(111.8)
Corporation tax	190.3	161.8	370.1
Deferred tax
Current year	(44.1)	(16.3)	(49.0)
Prior years	(17.4)	(4.5)	2.8
Deferred tax	(61.5)	(20.8)	(46.2)
Tax charge	£ 128.8	£ 141.0	£ 323.9

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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