INCOME TAXES	9 Months Ended
Sep. 30, 2017
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES: The effective tax rate for the three months ended September 30, 2017 and 2016 was 32.8% and (2.7)%, respectively. The effective tax rate for the nine months ended September 30, 2017 and 2016 was 19.1% and (1.1)%, respectively. The fluctuation in the effective tax rates is primarily attributable to the impact of the percentage of depletion on the respective periods' pre-tax income. The effective rate for the three and nine months ended September 30, 2017 and 2016 differs from the U.S. federal statutory rate of 35% primarily due to the income tax benefit for excess percentage depletion.

INCOME TAXES

9 Months Ended

Sep. 30, 2017

INCOME TAXES:

The effective tax rate for the three months ended September 30, 2017 and 2016 was 32.8% and (2.7)%, respectively. The effective tax rate for the nine months ended September 30, 2017 and 2016 was 19.1% and (1.1)%, respectively. The fluctuation in the effective tax rates is primarily attributable to the impact of the percentage of depletion on the respective periods' pre-tax income.

The effective rate for the three and nine months ended September 30, 2017 and 2016 differs from the U.S. federal statutory rate of 35% primarily due to the income tax benefit for excess percentage depletion.