Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net income	$ 48,179	$ 252,515	$ 411,803	$ 538,783
Other comprehensive income:
Unrealized gain (loss) on available for sale securities	119	(160)	115	(75)
Net gain on pension and other postretirement benefits	400	242	1,200	691
Total other comprehensive income	519	82	1,315	616
Comprehensive income	$ 48,698	$ 252,597	$ 413,118	$ 539,399