Income Tax (Tables)

9 Months Ended

Sep. 30, 2016

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	Three Months Ended September 30,						Nine Months Ended September 30,
Dollars in thousands	2016			2015			2016			2015
Income taxes at statutory rates (federal and state)	$	(5,339	)	$	(4,473	)	$	20,620		$	15,848
Increase (decrease):
Differences required to be flowed-through by regulatory commissions	(381		)	(378		)	1,202			1,036
Other, net	246			298			(528		)	(940		)
Total provision (benefit) for income taxes	$	(5,474	)	$	(4,553	)	$	21,294		$	15,944
Effective tax rate	40.5		%	40.5		%	41.0		%	39.9		%