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BENEFIT PLANS - Weighted-Average Actuarial Assumptions (Detail) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Other Postretirement Benefit Plans, Defined Benefit |  |  |  |
Weighted-average actuarial assumptions: |  |  |  |
Discount rate - net periodic benefit cost |  | 4.25% | 3.75% | 4.25%
Discount rate - benefit obligations |  | 3.25% | 4.25% | 3.75%
Health care cost trend rates | [1] | 7.50% | 7.40% | 5.40%
Defined benefit plan, ultimate health care cost trend rate |  | 3.80% | 4.10% | 4.50%
Defined benefit plan number of years that rate reaches ultimate trend rate |  | 54 years | 61 years | 77 years
Japan | Pension Plan |  |  |  |
Weighted-average actuarial assumptions: |  |  |  |
Discount rate - net periodic benefit cost |  | 1.25% | 1.25% | 1.25%
Discount rate - benefit obligations |  | 0.75% | 1.25% | 1.25%
Expected long-term return on plan assets |  | 2.00% | 2.00% | 2.00%
U.S. | Pension Plan |  |  |  |
Weighted-average actuarial assumptions: |  |  |  |
Discount rate - net periodic benefit cost |  | 4.25% | 3.75% | 4.25%
Discount rate - benefit obligations |  | 3.25% | 4.25% | 3.75%
Expected long-term return on plan assets |  | 6.25% | 6.50% | 6.75%
Rate of compensation increase |  | 4.00% | 4.00% | 4.00%
[1] | For the years 2019, 2018 and 2017, the health care cost trend rates are expected to trend down to 3.8% in 54 years, 4.1% in 61 years, and 4.5% in 77 years, respectively.

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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=118255775&loc=d3e1928-114920 + Details
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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 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=118255775&loc=d3e1928-114920 + 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=118255775&loc=d3e1928-114920 + Details
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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=118255775&loc=d3e1928-114920 + 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=118255775&loc=d3e1928-114920 + Details
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