CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
NET INCOME	$ 22,791	$ 8,094
Derivative instruments:
Net unrealized gain (loss), net of tax expense	0	(96)
Reclassification of net realized loss, net of tax expense	328	409
Pension and other postretirement benefits activity, net of tax benefit	879	900
Total other comprehensive income	1,207	1,213
COMPREHENSIVE INCOME	23,998	9,307
Less: Comprehensive income attributable to noncontrolling interests	4,873	4,873
COMPREHENSIVE INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	19,125	4,434
APS
NET INCOME	33,149	14,472
Derivative instruments:
Net unrealized gain (loss), net of tax expense	0	(96)
Reclassification of net realized loss, net of tax expense	328	409
Pension and other postretirement benefits activity, net of tax benefit	752	857
Total other comprehensive income	1,080	1,170
COMPREHENSIVE INCOME	34,229	15,642
Less: Comprehensive income attributable to noncontrolling interests	4,873	4,873
COMPREHENSIVE INCOME ATTRIBUTABLE TO COMMON SHAREHOLDERS	$ 29,356	$ 10,769