Introduction (Tables)

6 Months Ended

Jun. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of New Accounting Pronouncements and Changes in Accounting Principles

The specific impacts of applying ASC 606 to revenues from contracts with customers on the financial statements of Southern Company, Alabama Power, Georgia Power, and Southern Company Gas compared to previously recognized guidance is shown below.

	For the Three Months Ended June 30, 2018									For the Six Months Ended June 30, 2018
Condensed Statements of Income	As Reported			Balances Without Adoption of ASC 606			Effect of Change			As Reported			Balances Without Adoption of ASC 606			Effect of Change
	(in millions)									(in millions)
Southern Company
Natural gas revenues	$	706		$	713		$	(7	)	$	2,314		$	2,307		$	7
Other revenues	395			393			2			808			805			3
Other operations and maintenance	1,559			1,546			13			3,008			2,985			23
Operating income	63			81			(18		)	1,439			1,452			(13		)
Other income (expense), net	78			67			11			138			118			20
Earnings (loss) before income taxes	(266		)	(259		)	(7		)	784			777			7
Income taxes (benefit)	(139		)	(137		)	(2		)	(25		)	(27		)	2
Consolidated net income (loss)	(127		)	(122		)	(5		)	809			804			5
Consolidated net income (loss) attributable to Southern Company	(154		)	(149		)	(5		)	784			779			5
Alabama Power
Other revenues	$	69		$	60		$	9		$	131		$	114		$	17
Other operations and maintenance	402			391			11			788			767			21
Operating income	380			382			(2		)	752			756			(4		)
Other income (expense), net	12			10			2			15			11			4
Georgia Power
Other revenues	$	120		$	97		$	23		$	227		$	189		$	38
Other operations and maintenance	457			437			20			863			828			35
Operating income (loss)	(472		)	(475		)	3			41			38			3
Other income (expense), net	35			38			(3		)	73			76			(3		)
Southern Company Gas
Natural gas revenues	$	710		$	717		$	(7	)	$	2,341		$	2,334		$	7
Operating income	49			56			(7		)	436			429			7
Earnings before income taxes	24			31			(7		)	407			400			7
Income taxes	55			57			(2		)	159			157			2
Net income (loss)	(31		)	(26		)	(5		)	248			243			5

	For the Six Months Ended June 30, 2018
Condensed Statements of Cash Flows	As Reported			Balances Without Adoption of ASC 606			Effect of Change
	(in millions)
Southern Company
Consolidated net income	$	809		$	804		$	5
Changes in certain current assets and liabilities:
Receivables	94			99			(5		)
Other current assets	(40		)	(45		)	5
Accrued taxes	213			215			(2		)
Other current liabilities	125			118			7
Georgia Power
Changes in certain current assets and liabilities:
Receivables	$	(103	)	$	(75	)	$	(28	)
Other current assets	25			(3		)	28
Southern Company Gas
Net income	$	248		$	243		$	5
Changes in certain current assets and liabilities:
Accrued taxes	38			40			(2		)
Other current liabilities	24			17			7

	At June 30, 2018
Condensed Balance Sheets	As Reported			Balances Without Adoption of ASC 606			Effect of Change
	(in millions)
Southern Company
Unbilled revenues	$	769		$	824		$	(55	)
Other accounts and notes receivable	621			622			(1		)
Other current assets	172			116			56
Accrued taxes	544			542			2
Other current liabilities	808			815			(7		)
Retained earnings	8,494			8,489			5
Southern Company Gas
Accrued income taxes	$	86		$	84		$	2
Other current liabilities	143			150			(7		)
Accumulated deficit	(202		)	(207		)	5

Schedule of Change in Asset Retirement Obligation

As of June 30, 2018, details of the AROs, including those related to the CCR Rule, included in the condensed balance sheets of Southern Company, Alabama Power, and Mississippi Power were as follows:

	Southern Company			Alabama Power			Mississippi Power
	(in millions)
Balance at December 31, 2017	$	4,824		$	1,709		$	174
Liabilities incurred	1			—			—
Liabilities settled	(97		)	(19		)	(15		)
Accretion	95			41			2
Cash flow revisions	1,493			1,451			15
Reclassification to held for sale	(148		)	—			—
Balance at June 30, 2018	$	6,168		$	3,182		$	176

Estimated Cost Of Decommissioning

In June 2018, Alabama Power completed an updated decommissioning cost site study for Plant Farley. The estimated costs of decommissioning based on the 2018 site study are as follows:

Decommissioning periods:
Beginning year	2037
Completion year	2076
	(in millions)
Site study costs:
Radiated structures	$	1,621
Non-radiated structures	99
Total site study costs	$	1,720

Schedule of Goodwill

The following table presents year-to-date changes in goodwill balances for Southern Company and Southern Company Gas:

	Goodwill
	Southern Company				Southern Company Gas
					Gas Distribution Operations			Gas Marketing Services			Total
	(in millions)
Balance at December 31, 2017	$	6,268			$	4,702		$	1,265		$	5,967
Impairment(a)	(42		)		—			(42		)	(42		)
Sale of Pivotal Home Solutions(a)	(242		)		—			(242		)	(242		)
Reclassification to held for sale(b)	(668		)		(668		)	—			(668		)
Balance at June 30, 2018	$	5,315		(c)	$	4,034		$	981		$	5,015

(a) On April 11, 2018, Southern Company Gas entered into a stock purchase agreement for the sale of Pivotal Home Solutions. In contemplation of the transaction, a goodwill impairment charge of $42 million was recorded in the first quarter 2018. On June 4, 2018, Southern Company Gas and Pivotal Home Solutions completed this transaction. See Note (J) under "Southern Company Gas" for additional information.

(b) Reflects goodwill associated with Elizabethtown Gas, Elkton Gas, and Florida City Gas, which were sold subsequent to June 30, 2018. See Note (J) under "Southern Company Gas" and "Assets Held for Sale" for additional information.

(c) Total does not add due to rounding.

Schedule of Goodwill and Other Intangible Assets

Other intangible assets were as follows:

	At June 30, 2018							At December 31, 2017
	Gross Carrying Amount		Accumulated Amortization			Other Intangible Assets, Net		Gross Carrying Amount		Accumulated Amortization			Other Intangible Assets, Net
	(in millions)							(in millions)
Southern Company
Other intangible assets subject to amortization:
Customer relationships(*)	$	223	$	(79	)	$	144	$	288	$	(83	)	$	205
Trade names(*)	70		(17		)	53		159		(17		)	142
Storage and transportation contracts	64		(44		)	20		64		(34		)	30
PPA fair value adjustments	456		(60		)	396		456		(47		)	409
Other	19		(5		)	14		17		(5		)	12
Total other intangible assets subject to amortization	$	832	$	(205	)	$	627	$	984	$	(186	)	$	798
Other intangible assets not subject to amortization:
Federal Communications Commission licenses	75		—			75		75		—			75
Total other intangible assets	$	907	$	(205	)	$	702	$	1,059	$	(186	)	$	873
Southern Power
Other intangible assets subject to amortization:
PPA fair value adjustments	$	456	$	(60	)	$	396	$	456	$	(47	)	$	409
Southern Company Gas
Other intangible assets subject to amortization:
Gas marketing services(*)
Customer relationships	$	156	$	(71	)	$	85	$	221	$	(77	)	$	144
Trade names	26		(6		)	20		115		(9		)	106
Wholesale gas services
Storage and transportation contracts	64		(44		)	20		64		(34		)	30
Total other intangible assets subject to amortization	$	246	$	(121	)	$	125	$	400	$	(120	)	$	280

(*) Balances as of June 30, 2018 reflect Southern Company Gas' sale of Pivotal Home Solutions. See Note (J) under "Southern Company Gas – Sale of Pivotal Home Solutions" for additional information.

Finite-lived Intangible Assets Amortization Expense

Amortization associated with other intangible assets was as follows:

	Three Months Ended		Six Months Ended
	June 30, 2018
	(in millions)
Southern Company	$	23	$	50
Southern Power	$	6	$	13
Southern Company Gas	$	14	$	31

Schedule of Cash and Cash Equivalents

The following tables provide a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed balance sheets that total to the amounts shown in the condensed statements of cash flows for the registrants that had restricted cash at June 30, 2018 and/or December 31, 2017:

	Southern Company		Southern Company Gas
	(in millions)
At June 30, 2018
Cash and cash equivalents	$	1,980	$	69
Cash and cash equivalents classified as assets held for sale	31		—
Restricted cash:
Other accounts and notes receivable	6		6
Total cash, cash equivalents, and restricted cash	$	2,017	$	75

	Southern Company		Southern Power		Southern Company Gas
	(in millions)
At December 31, 2017
Cash and cash equivalents	$	2,130	$	129	$	73
Restricted cash:
Other accounts and notes receivable	5		—		5
Deferred charges and other assets	12		11		—
Total cash, cash equivalents, and restricted cash	$	2,147	$	140	$	78

Restrictions on Cash and Cash Equivalents

The following tables provide a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed balance sheets that total to the amounts shown in the condensed statements of cash flows for the registrants that had restricted cash at June 30, 2018 and/or December 31, 2017:

	Southern Company		Southern Company Gas
	(in millions)
At June 30, 2018
Cash and cash equivalents	$	1,980	$	69
Cash and cash equivalents classified as assets held for sale	31		—
Restricted cash:
Other accounts and notes receivable	6		6
Total cash, cash equivalents, and restricted cash	$	2,017	$	75

	Southern Company		Southern Power		Southern Company Gas
	(in millions)
At December 31, 2017
Cash and cash equivalents	$	2,130	$	129	$	73
Restricted cash:
Other accounts and notes receivable	5		—		5
Deferred charges and other assets	12		11		—
Total cash, cash equivalents, and restricted cash	$	2,147	$	140	$	78