NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Post-retirement Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Post-retirement Benefits
Post-retirement plan assets	$ 38	$ 28
Fisher SERP \| Fisher
Post-retirement Benefits
Estimated projected benefit obligation	$ 20
Discount rate for projected benefit obligation (as a percent)	3.04%	4.11%
Benefit payments	$ 2	$ 2
Actuarial gain	(2)	1
Periodic pension expense	1	$ 1
Fisher SERP \| Fisher \| Accrued expenses
Post-retirement Benefits
Estimated projected benefit obligation	2
Fisher SERP \| Fisher \| Other long-term liabilities
Post-retirement Benefits
Estimated projected benefit obligation	18
Other Post-Retirement Plans
Post-retirement Benefits
Post-retirement plan assets	36
Deferred compensation plan liabilities	$ 33

Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

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-Name Accounting Standards Codification
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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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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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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Amount of liability for retirement benefits, classified as other.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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Amount of cost (reversal of cost) for pension and other postretirement benefits.

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