Defined benefit plan assumptions used calculating benefit obligation measurement date.

No definition available.

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- Definition

Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Measurement Date

+ References

No definition available.

+ Details

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

+ References

+ Details

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(2)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

+ Details

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Period Type:	instant

- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in CCYY format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (l)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Details

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- Details

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- Details

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Weighted Average Assumptions Used for Pension Plans (Detail)				12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine net periodic benefit cost/(income), Expected return on plan assets	5.20%	5.90%	5.90%
Pension plans
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine Measurement date				Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted average assumptions used to determine benefit obligations, Discount rate				3.41%	3.58%	4.00%
Weighted average assumptions used to determine benefit obligations, Rate of compensation increase				3.00%	3.00%	3.00%
Weighted average assumptions used to determine Measurement date				Jan. 01, 2018	Jan. 01, 2017	Jan. 01, 2016
Weighted average assumptions used to determine net periodic benefit cost/(income), Discount rate				3.58%	4.00%	4.25%
Weighted average assumptions used to determine net periodic benefit cost/(income), Expected return on plan assets				5.34%	8.00%	8.00%
Weighted average assumptions used to determine net periodic benefit cost/(income), Rate of compensation increase				3.00%	3.00%	3.00%
Postretirement Benefit Plans \| Benefit Obligations
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine Measurement date				Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted average assumptions used to determine benefit obligations, Discount rate				4.07%	3.36%	3.66%
Health care cost trend rate, Initial rate				6.50%	6.00%	6.50%
Health care cost trend rate, Ultimate rate				5.00%	5.00%	5.00%
Health care cost trend rate, Year trend reaches the ultimate rate				2025	2022	2023
Postretirement Benefit Plans \| Net Periodic Benefit Cost
Defined Benefit Plan Disclosure [Line Items]
Weighted average assumptions used to determine Measurement date				Jan. 01, 2018	Jan. 01, 2017	Jan. 01, 2016
Weighted average assumptions used to determine net periodic benefit cost/(income), Discount rate				3.36%	3.66%	3.83%
Health care cost trend rate, Initial rate				6.00%	6.50%	8.00%
Health care cost trend rate, Ultimate rate				5.00%	5.00%	5.00%
Health care cost trend rate, Year trend reaches the ultimate rate				2022	2023	2022