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Cash and Cash Equivalents, Restricted Cash and Restricted Cash - Asbestos Cash and Cash Equivalents, Restricted Cash and Restricted Cash - Asbestos (Tables) | 12 Months Ended
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Mar. 31, 2020
Cash and Cash Equivalents, Restricted Cash and Restricted Cash - Asbestos [Abstract] |
Cash and Cash Equivalents, Restricted Cash and Restricted Cash - Asbestos [Table Text Block] | The following table provides a reconciliation of Cash and cash equivalents, Restricted cash and Restricted cash - Asbestos reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the consolidated statements of cash flows:
| 31 March
(Millions of US dollars) | 2020 |  | 2019 |  | 2018 |  | 2017
Cash and cash equivalents | $ | 144.4 |  |  | $ | 78.7 |  |  | $ | 281.6 |  |  | $ | 78.9 |
Restricted cash | 5.0 |  |  | 5.1 |  |  | 5.0 |  |  | 5.0 |
Restricted cash - Asbestos | 36.4 |  |  | 39.8 |  |  | 26.6 |  |  | 108.9 |
Total cash and cash equivalents, restricted cash and restricted cash - Asbestos | $ | 185.8 |  |  | $ | 123.6 |  |  | $ | 313.2 |  |  | $ | 192.8 |

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- Definition Cash and Cash Equivalents, Restricted Cash and Restricted Cash - Asbestos [Abstract] + References No definition available. + Details
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- Definition Cash and Cash Equivalents, Restricted Cash and Restricted Cash - Asbestos [Table Text Block] + References No definition available. + Details
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