INCOME TAXES - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Valuation allowance for deferred tax assets	$ 11,000,000	$ 126,000,000
Decrease in valuation allowance for deferred tax assets	115,000,000
Income tax expense, allocated to other comprehensive income	1,000,000	0
Federal income tax expense (benefit)	1,000,000	0
Other comprehensive (income) loss, defined benefit plan, after reclassification adjustment, tax	123,000,000
Reduction in income tax benefits	32,000,000
Federal net operating loss carryforwards, subject to expiration	198,000,000
Federal net operating loss carryforwards, not subject to expiration	40,000,000
State income tax credit	44,000,000	40,000,000
Research and development credit carryforwards		4,000,000
Federal tax rate change	0	0	$ 71,000,000
Tax-related interest and penalties	0	0
Expense (benefit) for interest and penalties	0	$ 0	0
Alternative Minimum Tax Carryover
Income Taxes [Line Items]
Federal tax rate change			$ (6,000,000)
Federal
Income Taxes [Line Items]
Net operating loss carryforwards	347,000,000
Operating loss carryforward, net of attributable reductions	238,000,000
State
Income Taxes [Line Items]
Net operating loss carryforwards	$ 71,000,000