MERCHANDISE TRUSTS - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($) Security	Dec. 31, 2021 USD ($)
West Virginia Trust Receivable
Schedule Of Available For Sale Securities [Line Items]
Trust assets, fair value	$ 9,900,000		$ 10,300,000
Merchandise Trusts
Schedule Of Available For Sale Securities [Line Items]
Percentage of VIE for cancellable state	47.70%
Impairments	$ 0	$ 0
Merchandise Trusts | Variable Interest Entity, Primary Beneficiary
Schedule Of Available For Sale Securities [Line Items]
Trust assets, fair value	589,767,000		567,853,000
Purchases of available for sale securities	19,400,000	21,600,000
Sales, maturities and paydowns of available for sale securities	9,100,000	4,900,000
Other than temporary impairments loss		$ 136,000
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		6
Trust assets, cost		$ 300,000
Trust assets, fair value		200,000
Other than temporary impairments loss		$ 100,000
Merchandise Trusts | West Virginia Trust Receivable | Variable Interest Entity, Primary Beneficiary
Schedule Of Available For Sale Securities [Line Items]
Trust assets, fair value	$ 9,869,000		$ 10,292,000