CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
NET INCOME	$ 51,900	$ 27,579	$ 202,878	$ 126,531
Pension and other postretirement benefit adjustments, net of income taxes of $1,993 and $1,845 for the three months ended September 30, 2013 and 2012, and $5,915 and $5,494 for the nine months ended September 30, 2013 and 2012, respectively:
Amortization of net loss	4,500	4,131	13,359	12,305
Amortization of transition obligation	0	77	0	231
Amortization of prior service credit	(799)	(782)	(2,373)	(2,333)
Total other comprehensive income	3,701	3,426	10,986	10,203
COMPREHENSIVE INCOME	$ 55,601	$ 31,005	$ 213,864	$ 136,734