Number Of Consecutive Periods Of Highest Compensation Used To Determine Defined Benefit Pension Plan Benefits

No definition available.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

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- Definition

The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

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-Topic 220

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- Definition

After tax net amount of gain (loss) that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases (decreases) in other comprehensive income as they arise.

+ References

No definition available.

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- Definition

Amount after tax of cost (credit) due to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as a component of net periodic benefit cost.

+ References

No definition available.

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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)

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-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

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.

+ 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 (j)

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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-Subparagraph (d)(i)

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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- Definition

Costs and payments related to employee benefits and equity-based compensation, such as pension expense and contributions, other postretirement benefits expense and payments, stock or unit options expense, and amortization of restricted stock or unit.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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-Paragraph 28

-Subparagraph (a)

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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-Paragraph 2

-Subparagraph (bb)

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- Definition

Amount of purchases, (sales), issuances and (settlements) of financial instrument classified in shareholders' equity measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

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- Definition

The amount of cash or cash equivalents contributed by the entity to fund its pension plans.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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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.

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Employee Benefits - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Number of consecutive years of employee's compensation	5 years
Number of total years of employee's compensation	10 years
Accumulated benefit obligation	$ 104,300,000	$ 88,300,000
Projected benefit obligation	113,124,000	95,969,000	102,454,000
Net periodic benefit cost	736,000	2,832,000	3,919,000
Fair value of asset transfer from Level 1 to Level 2 on recurring basis	0
Purchases, transfers or sales of level 3 plan assets	0
Pension Contributions	0us-gaap_PensionContributions
Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	3,500,000	2,800,000
Net periodic benefit cost	400,000	400,000	500,000
Defined benefit plan in accumulated other comprehensive gain/loss before tax	2,100,000	1,500,000
Thrift Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions to the Thrift Plan	3.50%
Compensation expense	1,300,000	1,400,000	1,300,000
Marketable Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted asset allocation minimum	50.00%
Targeted asset allocation maximum	70.00%
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Targeted asset allocation minimum	30.00%
Targeted asset allocation maximum	50.00%
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss included in accumulated other comprehensive income (loss)				(1,900,000)
Prior service credit expected recognized Amount				$ 100,000