Defined Benefit Plan, Settlements

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- Definition

Defined Benefit Plan, Settlements Expensed

+ References

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- References

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- Definition

The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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-Publisher FASB
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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

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- Definition

Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

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- Definition

The amount of increase related to special termination benefits offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. A situation involving termination benefits may also involve a curtailment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Termination Benefits
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- Definition

Amount before tax of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) related to pension and other postretirement benefit plans.

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- Definition

Amount before tax of gain (loss) adjustment to other comprehensive income (loss) resulting from settlement or curtailment of defined benefit pension and other postretirement defined benefit plans.

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount before tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

+ References

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for net transition asset (obligation) related to pension and other postretirement benefit plans.

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Period expense related to postemployment benefits.

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No definition available.

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Employee Benefit Plans (Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Termination benefit charge		$ 2,500
Pension Benefits
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Net actuarial (gain) loss experienced during the year				$ (394)	$ 10,495	$ (14,138)
Net actuarial loss recognized as expense				(30,478)	(25,433)	(8,934)
Prior service cost recognized as expense				0	(246)	(311)
Curtailment loss				0	(8,749)	0
Total recognized in other comprehensive income (loss)				(30,872)	(23,933)	(23,383)
Settlement charges				27,300	7,600
Settlement charges expensed					3,700
Termination benefit charge				0	2,477	0
Curtailment gain				0	8,496
Settlement charge				29,767	4,082	161
Amortization of net actuarial loss				3,352
Postretirement Benefits
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Net actuarial (gain) loss experienced during the year				(645)	7,649	(8,057)
Net actuarial loss recognized as expense				0	1,908	550
Prior service cost recognized as expense				(4,071)	0	0
Transition obligation recognized as expense				0	(48)	(283)
Total recognized in other comprehensive income (loss)				(4,716)	9,509	(7,790)
Termination benefit charge				0	0
Curtailment gain				0	0
Amortization of prior service credit				(515)
Nonqualified Supplemental Retirement Plans
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Settlement charges	$ 2,500	1,800			400	600
Settlement charges expensed						200
Long-term Disability Plan
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Expense related to long-term disability plan				$ 200	$ 200	200
Alabama Gas Corporation \| Nonqualified Supplemental Retirement Plans
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Settlement charges						$ 400
Alagasco
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Curtailment gain		$ 300
Black Warrior Basin
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract]
Curtailment gain			$ 1,200