ACCOUNTING POLICIES (Narrative) (Details)					3 Months Ended		9 Months Ended
	Jun. 01, 2022 USD ($)	May 31, 2022 USD ($)	Dec. 31, 2021 USD ($)		Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) property	Sep. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Apr. 28, 2022	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Organization And Significant Accounting Policies [Line Items]
Number of branches | property							32
Financing receivable, allowance for credit loss			$ 29,105,000	[1]	$ 31,956,000	$ 30,386,000	$ 31,956,000	$ 30,386,000	$ 30,209,000		$ 31,265,000	$ 36,345,000
Cumulative effect adjustment			411,881,000	[1]	391,808,000	408,629,000	391,808,000	408,629,000	$ 398,637,000		$ 406,940,000	$ 390,554,000
Net income					5,054,000	3,939,000	14,656,000	23,597,000
Gain (loss) on sale of mortgage loans							2,790,000	0
Salaries and benefits					12,594,000	$ 9,032,000	32,792,000	$ 27,214,000
Securities available for sale, at fair value			271,332,000	[1]	238,891,000		238,891,000
Loans held for investment			2,339,986,000	[1]	$ 2,737,086,000		$ 2,737,086,000
Southern Trust Mortgage [Member]
Organization And Significant Accounting Policies [Line Items]
Notes receivable			8,500,000
Southern Trust Mortgage [Member]
Organization And Significant Accounting Policies [Line Items]
Payments to acquire equity method investments			$ 1,600,000
Common Stock | Southern Trust Mortgage [Member]
Organization And Significant Accounting Policies [Line Items]
Percentage of equity investment and preferred stock of STM						43.28%		43.28%
Preferred Stock | Southern Trust Mortgage [Member]
Organization And Significant Accounting Policies [Line Items]
Percentage of equity investment and preferred stock of STM					100.00%	100.00%	100.00%	100.00%
Paycheck Protection Program Loans [Member]
Organization And Significant Accounting Policies [Line Items]
Financing receivable, allowance for credit loss					$ 0		$ 0
Primis Mortgage (f.k.a. SeaTrust)
Organization And Significant Accounting Policies [Line Items]
Payments to acquire business	$ 7,000,000	$ 7,000,000
Short term borrowings	$ 19,254,000	$ 19,254,000
Voting interest agreed to acquire (as a percent)										100.00%
Capital Stock Acquired (as a percent)		100.00%
Virginia [Member]
Organization And Significant Accounting Policies [Line Items]
Number of branches | property							30
Maryland
Organization And Significant Accounting Policies [Line Items]
Number of branches | property							2

[1] Derived from audited consolidated financial statements