Employee Postretirement Benefits - Schedule of Assumptions Used to Determine Benefit (Detail)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.55%	2.77%
Rate of compensation increase	3.79%	3.05%
Discount rate	2.77%	2.37%	3.21%
Expected long-term return on plan assets	6.50%	6.70%	7.00%
Rate of compensation increase	3.05%	3.08%	3.79%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.53%	2.84%
Rate of compensation increase	3.79%	3.04%
Discount rate	2.84%	2.47%	3.32%
Rate of compensation increase	3.04%	3.07%	3.79%
Healthcare cost trend rate
Ultimate rate	4.00%	4.50%	4.50%
Year rate reaches ultimate trend rate	2045	2038	2038
Other Postretirement Benefits [Member] \| Immediate Rate [Member]
Healthcare cost trend rate
Immediate rate	6.39%	5.61%
Other Postretirement Benefits [Member] \| Initial Rate [Member]
Healthcare cost trend rate
Immediate rate	5.61%	5.74%	6.03%
Other Postretirement Benefits [Member] \| Ultimate Trend Rate Per Actuary [Member]
Healthcare cost trend rate
Ultimate rate	4.00%	4.00%
Year rate reaches ultimate trend rate	2047	2045

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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.

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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.

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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.

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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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2919-114920

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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.

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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.

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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.

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- Definition

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

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

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