Expected rate of compensation increases (for pay-related plans).

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Projected Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6522206

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503904

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- Definition

Net increase or decrease in the plan benefit obligation during the reporting period.

+ References

+ Details

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- Details

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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.

+ Details

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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.

+ Details

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

+ Details

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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- Definition

Defined benefit plan, number of plan participants

+ References

No definition available.

+ Details

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- Details

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Pension Plans and Defined Contribution Plan - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended
	Dec. 10, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 224,086,000	$ 183,069,000	$ 196,521,000
Benefit Obligation, Increase (Decrease)		8,600,000
Compensation increase rate		0.00%	0.00%	0.00%
Cash contribution to pension plans in next fiscal year	2,000,000
Company contributions		5,500,000	5,300,000	5,300,000
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Active associates in the pension plan		2,600
Accumulated benefit obligation		224,100,000	183,100,000
Estimated net actuarial loss that will be amortized from accumulated other comprehensive loss		5,800,000
Estimated prior service cost that will be amortized from accumulated other comprehensive loss		$ 300,000
Pension Plans [Member] \| General Plan Assets [Member] \| Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		50.00%
Pension Plans [Member] \| General Plan Assets [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		26.00%
Pension Plans [Member] \| General Plan Assets [Member] \| Domestic Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		14.00%
Pension Plans [Member] \| General Plan Assets [Member] \| Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		10.00%
Pension Plans [Member] \| Union Plan Assets [Member] \| Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		20.00%
Pension Plans [Member] \| Union Plan Assets [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		50.00%
Pension Plans [Member] \| Union Plan Assets [Member] \| Domestic Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		20.00%
Pension Plans [Member] \| Union Plan Assets [Member] \| Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocations for plan assets		10.00%