Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Accumulated Amortization	$ 280	$ 235
Common stock, par value (in dollars per share)	$ 5	$ 5
Common stock, shares authorized (in shares)	1,500,000,000	1,500,000,000
Southern Power
Accumulated Amortization	$ 69	$ 61
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000	1,000,000
Common stock, shares outstanding (in shares)	1,000	1,000
Southern Power \| 2.375% due 2020
Fixed stated interest rate of debt obligation	2.375%	2.375%
Southern Power \| 2.50% due 2021
Fixed stated interest rate of debt obligation	2.50%	2.50%
Southern Power \| 1.00% due 2022
Fixed stated interest rate of debt obligation	1.00%	1.00%
Southern Power \| 2.75% due 2023
Fixed stated interest rate of debt obligation	2.75%	2.75%
Southern Power \| Variable rate (3.34% at 12/31/18) due 2020
Fixed stated interest rate of debt obligation		3.34%
Southern Company Gas
Accumulated Amortization	$ 176	$ 145
Common stock, par value (in dollars per share)	$ 0.01	$ 10,000.00
Common stock, shares authorized (in shares)	100,000,000	100
Common stock, shares outstanding (in shares)	100	100
Weighted Average \| Southern Power \| Weighted average interest rate 4.12% at 12/31/19 due 2025-2046
Fixed stated interest rate of debt obligation	4.12%
Minimum \| Southern Power \| Weighted average interest rate 4.12% at 12/31/19 due 2025-2046
Fixed stated interest rate of debt obligation	1.85%	0.00%
Maximum \| Southern Power \| Weighted average interest rate 4.12% at 12/31/19 due 2025-2046
Fixed stated interest rate of debt obligation	5.25%	0.00%

Face amount or stated value per share of common stock.

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