Capital (Details) $ / shares in Units, $ in Millions |
3 Months Ended | |||
|---|---|---|---|---|
|
Mar. 15, 2019
USD ($)
$ / shares
|
Mar. 16, 2018
USD ($)
$ / shares
|
Mar. 31, 2019
$ / shares
shares
|
Mar. 31, 2018
$ / shares
shares
|
|
| Class of Stock [Line Items] | ||||
| Payments of dividends | $ | $ 46.5 | $ 31.7 | ||
| Dividend paid per sub-share (in dollars per share) | $ 6 | $ 4.05 | ||
| Sub Shares | ||||
| Class of Stock [Line Items] | ||||
| Ratio of certificates to sub-shares | 0.0003333333333 | |||
| Number of shares repurchased and retired (in shares) | shares | 6,258 | 13,146 | ||
| Cash Dividend | Sub Shares | ||||
| Class of Stock [Line Items] | ||||
| Dividend paid per sub-share (in dollars per share) | $ 1.75 | $ 1.05 | ||
| Special Dividend | Sub Shares | ||||
| Class of Stock [Line Items] | ||||
| Dividend paid per sub-share (in dollars per share) | $ 4.25 | $ 3 | ||
| X | ||||||||||
- Definition Sub-share Certificate Equivalent Ratio No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares that have been repurchased and retired during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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