FAIR VALUE MEASUREMENTS (Tables)

6 Months Ended

Jun. 30, 2018

FAIR VALUE MEASUREMENTS

Schedule of assets measured at fair value on recurring basis

	As of June 30, 2018
	Fair Value Measurements Using
	Quoted Prices in		Significant Other		Significant
	Active Markets for		Observable		Unobservable
	Identical Assets		Inputs		Inputs
(in thousands)	(Level 1)		(Level 2)		(Level 3)		Total
Fixed income securities - available-for-sale
U.S. government	$	—	$	149,165	$	—	$	149,165
U.S. agency		—		30,256		—		30,256
Non-U.S. govt. & agency		—		7,895		—		7,895
Agency MBS		—		354,345		—		354,345
ABS/CMBS*		—		100,194		—		100,194
Corporate		—		624,686		—		624,686
Municipal		—		444,071		—		444,071
Total fixed income securities - available-for-sale	$	—	$	1,710,612	$	—	$	1,710,612
Equity securities		386,603		—		—		386,603
Total	$	386,603	$	1,710,612	$	—	$	2,097,215

	As of December 31, 2017
	Fair Value Measurements Using
	Quoted Prices in		Significant Other		Significant
	Active Markets for		Observable		Unobservable
	Identical Assets		Inputs		Inputs
(in thousands)	(Level 1)		(Level 2)		(Level 3)		Total
Fixed income securities - available-for-sale
U.S. government	$	—	$	91,689	$	—	$	91,689
U.S. agency		—		18,778		—		18,778
Non-U.S. govt. & agency		—		7,588		—		7,588
Agency MBS		—		328,471		—		328,471
ABS/CMBS*		—		70,526		—		70,526
Corporate		—		519,022		—		519,022
Municipal		—		636,165		—		636,165
Total fixed income securities - available-for-sale	$	—	$	1,672,239	$	—	$	1,672,239
Equity securities		400,492		—		—		400,492
Total	$	400,492	$	1,672,239	$	—	$	2,072,731

* Non-agency asset-backed and commercial mortgage-backed