INCOME TAXES (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Effective income tax rate (as a percent)	23.30%	29.20%		44.40%
Reconciliation of federal income taxes and reported income taxes
Statutory federal tax provision (benefit)	$ (6,500)	$ 30,800
State income taxes	6,400	5,600
Income tax credits	(25,000)	(20,300)
Change in uncertain tax positions	2,500	1,000
Foreign tax benefit	14,300	(5,600)
Other	3,852	14,500
Income tax expense (benefit)	(4,448)	$ 26,000
Unrecognized tax benefits
Net uncertain tax benefit positions that would increase (reduce) effective income tax rate, if recognized	$ 49,500			$ 52,000
Forecast
Effective income tax rate (as a percent)			23.30%