Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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INVESTMENTS - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net investment income
Gross investment income									$ 73,988	$ 66,614	$ 59,794
Less investment expenses									(5,118)	(4,529)	(4,918)
Net Investment Income	$ 17,775	$ 17,532	$ 16,998	$ 16,565	$ 16,962	$ 16,314	$ 14,577	$ 14,232	68,870	62,085	54,876
Debt securities
Net investment income
Gross investment income									60,364	54,491	48,343
Equity securities
Net investment income
Gross investment income									9,950	9,814	10,506
Cash and Short-term Investments
Net investment income
Gross investment income									$ 3,674	$ 2,309	$ 945