Pension and Other Employee Benefits (Schedule of Investment Allocation Ranges) (Details)	Dec. 31, 2019
Minimum [Member] | Global equity
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	30.00%
Minimum [Member] | U.S. equities
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	20.00%
Minimum [Member] | International equities
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	10.00%
Minimum [Member] | Fixed income securities
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	20.00%
Minimum [Member] | Cash and cash equivalents
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	0.00%
Minimum [Member] | Private equity and private real estate funds
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	10.00%
Minimum [Member] | Real assets
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	0.00%
Minimum [Member] | Other (including absolute return funds)
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	5.00%
Maximum [Member] | Global equity
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	60.00%
Maximum [Member] | U.S. equities
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	35.00%
Maximum [Member] | International equities
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	25.00%
Maximum [Member] | Fixed income securities
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	45.00%
Maximum [Member] | Cash and cash equivalents
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	10.00%
Maximum [Member] | Private equity and private real estate funds
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	20.00%
Maximum [Member] | Real assets
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	4.00%
Maximum [Member] | Other (including absolute return funds)
Defined Benefit Plans and PRB Plans [Line Items]
Investment policy asset allocation ranges minimum	15.00%