Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Gain or Loss

-URI http://asc.fasb.org/extlink&oid=6514294

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(4)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Gain or Loss

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- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512136

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512171

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Topic 715

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-Paragraph 1

-Subparagraph (h)(3)

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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

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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Amount of net gain (loss) recognized in net periodic benefit cost due to settlements and curtailments. Curtailments result from 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. Settlements result from 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.

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ 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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-Glossary Service Cost (Component of Net Periodic Pension Cost)

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-Publisher FASB

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-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

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Defined Benefit Plans - Components of Net Periodic Benefit Cost for Pension and Postretirement Benefits (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended			3 Months Ended	6 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014	Jun. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Recognition of actuarial losses	$ 13.7	$ 5.2	$ 42.2
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	10.4	11.4
Interest cost	32.9	30.1
Recognition of actuarial losses	133.1	(73.0)
Amortization of prior service cost (credits)	0.1
Pension Benefits \| Net Periodic Benefit Cost
Defined Benefit Plan Disclosure [Line Items]
Service cost	10.4	11.4	12.1
Interest cost	32.9	30.1	30.7
Expected return on plan assets	(42.2)	(41.8)	(36.8)
Recognition of actuarial losses	12.5	0.8	30.6
Amortization of prior service cost (credits)	0.1	0.1	0.3
Curtailment and settlement losses		0.1
Net periodic benefit cost	13.7	0.7	36.9
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.1	0.3
Interest cost	0.8	1.7
Recognition of actuarial losses	3.9	(0.3)		0.6	4.0
Amortization of prior service cost (credits)	(14.0)
Postretirement Benefits \| Net Periodic Benefit Cost
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.1	0.3	0.5
Interest cost	0.8	1.7	3.9
Recognition of actuarial losses	1.2	4.4	11.6
Amortization of prior service cost (credits)	(27.6)	(27.4)	(2.6)
Curtailment and settlement losses		0.1
Net periodic benefit cost	$ (25.5)	$ (20.9)	$ 13.4