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Non-controlling Interest In Subsidiaries (Narrative) (Details) - GBPC | 12 Months Ended
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Dec. 31, 2020 $ / shares
Noncontrolling Interest [Line Items] |
Preferred Stock, Dividend Payment Terms | 6.0 per cent per annum fixed cumulative preferential dividend to be paid semi-annually
Preferred Stock, Redemption Terms | The preferred shares are redeemable by GBPC after June 17, 2021
Non-voting Cumulative Redeemable Variable Perpetual Preferred Shares |
Noncontrolling Interest [Line Items] |
Preferred Stock, Redemption Price Per Share | $ 1,000
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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