INCOME TAXES - Statutory Tax Rate and Effective Tax Rate (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Examination [Line Items]
Statutory federal tax	$ 38,621	$ 45,405	$ 28,196
Statutory federal tax, effective tax rate, percent	21.00%	21.00%	21.00%
State income taxes, net of federal benefit	$ 4,635	$ 4,980	$ 1,470
State income taxes, net of federal benefit, effective tax rate, percent	2.50%	2.30%	1.10%
Share-based compensation - windfall	$ (26)	$ (1,835)	$ (415)
Share-based compensation - windfall, effective tax rate, percent	0.00%	(0.80%)	(0.30%)
Research and development and jobs credits	$ (819)	$ (503)	$ (370)
Research and development and jobs credits, effective tax rate, percent	(0.40%)	(0.20%)	(0.30%)
Executive compensation	$ 1,470	$ 2,652	$ 966
Executive compensation, effective tax rate, percent	0.80%	1.20%	0.70%
Charitable donations	$ (4,316)	$ 0	$ 0
Charitable donations, effective tax rate, percent	(2.30%)	0.00%	0.00%
Valuation allowance	$ 396	$ 468	$ 1,342
Valuation allowance, effective tax rate, percent	0.20%	0.20%	1.00%
Other permanent differences	$ 427	$ 808	$ 16
Other permanent differences, effective tax rate, percent	0.20%	0.40%	0.00%
Provision for income taxes	$ 40,491	$ 52,098	$ 31,406
Provision for income taxes, effective tax rate, percent	22.00%	24.10%	23.40%
Hong Kong
Income Tax Examination [Line Items]
Foreign taxes	$ 75	$ 91	$ 94
Foreign taxes, effective tax rate, percent	0.00%	0.00%	0.10%
Singapore
Income Tax Examination [Line Items]
Foreign taxes	$ 28	$ 32	$ 107
Foreign taxes, effective tax rate, percent	0.00%	0.00%	0.10%

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