REGULATORY CAPITAL (Schedule of Regulatory Capital Amounts and Ratios) (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
The Bank [Member]
Total Capital
Total Capital (to risk-weighted assets)	$ 600,478	$ 571,509
Total Capital (to risk-weighted assets) ratio	14.81	13.76
Minimum Capital required to be well-capitalized	$ 405,587	$ 415,487
Minimum Capital required to be well-capitalized, ratio	10.00	10.00
Minimum amount of capital for adequacy purposes	$ 324,469	$ 332,389
Minimum amount of capital for adequacy purposes, ratio	8.00	8.00
Tier I Capital (to risk-weighted assets)
Tier 1 Capital (to risk-weighted assets)	$ 549,575	$ 527,833
Tier 1 Capital (to risk-weighted assets) ratio	13.55	12.70
Minimum Tier 1 Capital required to be well-capitalized	$ 324,469	$ 332,389
Minimum Tier 1 Capital required to be well-capitalized, ratio	8.00	8.00
Minimum amount of Tier 1 Capital for adequacy purposes	$ 243,352	$ 249,292
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	6.00	6.00
Common equity tier I
Common equity tier 1 (to risk-weighted assets)	$ 549,540	$ 527,832
Common equity tier I (to risk-weighted assets) ratio	13.55	12.70
Minimum Common equity tier I required to be well-capitalized	$ 263,631	$ 270,066
Minimum common equity tier I required to be well-capitalized, ratio	6.50%	6.50%
Minimum amount of common equity tier I for adequacy purposes	$ 182,514	$ 186,969
Minimum amount of common equity tier I for adequacy purposes, ratio	4.50%	4.50%
Tier I Leverage Capital (to average assets)
Tier 1 Capital(to average assets)	$ 549,575	$ 527,833
Tier 1 Capital (to average assets) ratio	9.71	10.63
Minimum Tier 1 Capital required to be well-capitalized	$ 283,083	$ 248,252
Minimum Tier 1 Capital required to be well-capitalized, ratio	5.00	5.00
Minimum amount of Tier 1 Capital for adequacy purposes	$ 226,466	$ 198,602
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00	4.00
The Bank [Member] \| Conservation Buffer [Member]
Total Capital
Minimum amount of capital for adequacy purposes	$ 425,866	$ 436,261
Minimum amount of capital for adequacy purposes, ratio	10.50	10.50
Tier I Capital (to risk-weighted assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 344,749	$ 353,164
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	8.50	8.50
Common equity tier I
Minimum amount of common equity tier I for adequacy purposes	$ 283,911	$ 290,841
Minimum amount of common equity tier I for adequacy purposes, ratio	7.00%	7.00%
Tier I Leverage Capital (to average assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 226,466	$ 198,602
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00	4.00
Parent Company [Member]
Total Capital
Total Capital (to risk-weighted assets)	$ 716,210	$ 590,614
Total Capital (to risk-weighted assets) ratio	17.67	14.20
Minimum amount of capital for adequacy purposes	$ 324,322	$ 332,783
Minimum amount of capital for adequacy purposes, ratio	8.00	8.00
Tier I Capital (to risk-weighted assets)
Tier 1 Capital (to risk-weighted assets)	$ 483,535	$ 463,521
Tier 1 Capital (to risk-weighted assets) ratio	11.93	11.14
Minimum amount of Tier 1 Capital for adequacy purposes	$ 243,242	$ 249,587
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	6.00	6.00
Common equity tier I
Common equity tier 1 (to risk-weighted assets)	$ 483,500	$ 463,520
Common equity tier I (to risk-weighted assets) ratio	11.93	11.14
Minimum amount of common equity tier I for adequacy purposes	$ 182,431	$ 187,190
Minimum amount of common equity tier I for adequacy purposes, ratio	4.50%	4.50%
Tier I Leverage Capital (to average assets)
Tier 1 Capital(to average assets)	$ 483,535	$ 463,521
Tier 1 Capital (to average assets) ratio	8.53	9.33
Minimum amount of Tier 1 Capital for adequacy purposes	$ 226,624	$ 198,792
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00	4.00
Parent Company [Member] \| Conservation Buffer [Member]
Total Capital
Minimum amount of capital for adequacy purposes	$ 425,673	$ 436,778
Minimum amount of capital for adequacy purposes, ratio	10.50	10.50
Tier I Capital (to risk-weighted assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 344,592	$ 353,582
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	8.50	8.50
Common equity tier I
Minimum amount of common equity tier I for adequacy purposes	$ 283,782	$ 291,185
Minimum amount of common equity tier I for adequacy purposes, ratio	7.00%	7.00%
Tier I Leverage Capital (to average assets)
Minimum amount of Tier 1 Capital for adequacy purposes	$ 226,624	$ 198,792
Minimum amount of Tier 1 Capital for adequacy purposes, ratio	4.00	4.00

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