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Non-controlling Interest In Subsidiaries (Narrative) (Details) - 1 months ended Jun. 30, 2019 - GBPC $ in Millions | USD ($) | $ / shares
--- | --- | ---
Noncontrolling Interest [Line Items] |  |
Preferred Stock, Redemption Price Per Share | $ / shares |  | $ 1,000
Preferred Stock, Dividend Payment Terms | 6.0 per cent per annum fixed cumulative preferential dividend to be paid semi-annually, with the first payment scheduled for January 2020 |
USD Debt |  |
Noncontrolling Interest [Line Items] |  |
Conversion of Stock, Amount Issued | $ 10 |
USD preferred shares |  |
Noncontrolling Interest [Line Items] |  |
Conversion of Stock, Amount Issued | $ 10 |
Non-voting Cumulative Redeemable Variable Perpetual Preferred Shares | USD Debt |  |
Noncontrolling Interest [Line Items] |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 4.00%
Non-voting Cumulative Redeemable Variable Perpetual Preferred Shares | USD preferred shares |  |
Noncontrolling Interest [Line Items] |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 6.00%

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