Business Acquisition, Conversion Ratio, Percentage of Underlying Stock Award Units

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Period Type:	duration

- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

+ Details

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Balance Type:	debit
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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Stock Compensation - Merger Stock Compensation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	6 Months Ended		12 Months Ended
	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Jul. 01, 2016
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period			3 years
Equity instrument, granted (in shares)			0.7
Total compensation cost for award recognized in income			$ 27	$ 25
Total compensation cost for award recognized in income, tax benefit			$ 7	$ 10
Total unrecognized compensation cost related to award, weighted average period			16 months
Parent Company \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instrument, granted (in shares)	0.7
Equity instrument granted in period, weighted average grant date fair value (in dollars per share)	$ 53.83		$ 43.81	$ 49.25
Merger-related expenses			$ 13
Southern Company Gas
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Merger-related expenses	$ 41		$ 0	$ 0
Southern Company Gas \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period			3 years
Southern Company Gas \| Restricted Stock Units (RSUs), Pre-acquisition
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost for award recognized in income	13		$ 2	8
Total compensation cost for award recognized in income, tax benefit	4		$ 1	4
Southern Company Gas \| Change In Control Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.00%
Total compensation cost for award recognized in income	4		$ 5	12
Tax credit carryforward	$ 1		2	$ 6
Compensation not yet recognized			$ 2
Total unrecognized compensation cost related to award, weighted average period			6 months
Southern Company Gas \| Predecessor
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Merger-related expenses		$ 56
Southern Company Gas \| Predecessor \| Cash and Stock-based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost for award recognized in income		$ 24
Southern Company \| Southern Company Gas
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Business acquisition share price (in dollars per share)					$ 66
Conversion ratio, percentage of underlying stock award units					125.00%