Defined benefit plan effective date of plan amendment.

No definition available.

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- Definition

Defined benefit plan, fair value of investments.

+ References

No definition available.

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- Definition

Number of noncontributory defined benefit pension plans.

+ References

No definition available.

+ 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

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ 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 (l)

-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 Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

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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

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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

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-Publisher FASB

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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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Employee Benefit Plans - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 27, 2014 Pension_Plan	Dec. 28, 2013	Dec. 29, 2012	Dec. 26, 2015
Defined Benefit Plan Disclosure [Line Items]
Expense for defined contribution plans	$ 3,800,000	$ 2,300,000	$ 2,200,000
Number of noncontributory defined benefit pension plans	2
Effective date of plan amended to eliminate	Jan. 01, 2014
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan fair value of investments	0	0
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	30.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	63.00%
Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	5.00%
Precious Metals [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation	2.00%
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend rates	6.00%	7.00%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Assumed health care cost trend rates	8.00%	9.00%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss expected to be amortized from AOCI	300,000
Pension Benefits [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to plans				1,100,000
Healthcare & Life Ins [Member]
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss expected to be amortized from AOCI	100,000
Healthcare & Life Ins [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to plans				$ 1,000,000