The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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GOODWILL AND INTANGIBLE ASSETS - Intangible assets (Details) - USD ($) $ in Thousands		12 Months Ended
	Jun. 17, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Finite-lived intangible assets
Gross carrying amount		$ 74,832	$ 72,930
Accumulated amortization		(53,966)	(48,556)
Total		20,866	24,374
Amortization of intangible assets		5,410	5,855	$ 6,504
FNBC Bank & Trust
Finite-lived intangible assets
Intangible assets	$ 1,901
Core deposit intangibles
Finite-lived intangible assets
Gross carrying amount		58,913	57,012
Accumulated amortization		(44,723)	(40,603)
Total		14,190	16,409
Core deposit intangibles \| FNBC Bank & Trust
Finite-lived intangible assets
Intangible assets	$ 1,901
Estimated useful life	10 years
Customer relationship intangibles
Finite-lived intangible assets
Gross carrying amount		15,919	15,918
Accumulated amortization		(9,243)	(7,953)
Total		$ 6,676	$ 7,965