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Earnings/(Loss) per share (Details) - shares |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Apr. 09, 2019 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Earnings per share [abstract] |  |  |  |  |
Number of shares distributed in spin-off (in shares) | 488,200,000 |  |  |  |
Adjusted weighted average number of ordinary shares outstanding (in shares) |  | 488,200,000 | 488,200,000 | 488,200,000 | 488,200,000
Antidilutive securities excluded from computation (in shares) |  | 1,800,000 |  | 900,000 |

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- Definition Antidilutive Securities Excluded From Computation Of Earnings Per Share, Amount + References No definition available. + Details
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- Definition Number Of Shares Distributed In Spin-off + References No definition available. + Details
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- Definition The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2018-01-01 -Paragraph 70 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2018-03-01&anchor=para_70_b&doctype=Standard -URIDate 2018-03-16 + Details
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- References No definition available. + Details
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