MERCHANDISE TRUSTS - Additional Information (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($) security	Dec. 31, 2019 USD ($)
West Virginia Trust Receivable
Schedule Of Available For Sale Securities [Line Items]
Trust assets, fair value	$ 8,600		$ 9,700
Merchandise Trusts
Schedule Of Available For Sale Securities [Line Items]
Percentage of VIE for cancellable state	52.60%
Merchandise Trusts | Variable Interest Entity, Primary Beneficiary
Schedule Of Available For Sale Securities [Line Items]
Trust assets, fair value	$ 457,765		523,865
Purchases of available for sale securities	13,200	$ 21,300
Sales, maturities and paydowns of available for sale securities	11,100	$ 9,100
Merchandise Trusts | Variable Interest Entity, Primary Beneficiary | Other Than Temporarily Impaired Securities
Schedule Of Available For Sale Securities [Line Items]
Number of securities that incurred other than temporary impairment losses | security		89
Trust assets, cost		$ 91,900
Trust assets, fair value		89,600
Other than temporary impairments loss	0	$ 2,300
Merchandise Trusts | West Virginia Trust Receivable | Variable Interest Entity, Primary Beneficiary
Schedule Of Available For Sale Securities [Line Items]
Trust assets, fair value	$ 8,591		$ 9,651