INCOME TAXES - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income tax reconciliation [Abstract]
Income tax at Federal statutory rate		$ 20,796	$ 30,971	$ 29,027
State income taxes, net of Federal income taxes		2,742	708	1,510
Federal Rate Change	$ (27,255)	0	(27,255)	0
Stock Options		(1,293)	(2,927)	0
GILTI & FDII		1,027	0	0
Deemed Repatriation		(970)	1,389	0
Foreign Tax Credits		(1,136)	0	0
Domestic production activities deduction		0	(2,382)	(3,299)
Other		(709)	(2,087)	(276)
Total income tax provision		$ 20,457	$ (1,583)	$ 26,962

Effective Income Tax Rate Reconciliation, Global Intangible Low-Tax Income And Foreign-Derived Intangible Income

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

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