Income Tax (Tables)

6 Months Ended

Jun. 30, 2015

Income Tax Disclosure [Abstract]

Schedule of Components of Income Tax Expenses (Benefit)

	Three Months Ended June 30,						Six Months Ended June 30,
Dollars in thousands	2015			2014			2015			2014
Income tax at statutory rates (federal and state)	$	1,429		$	728		$	20,321		$	26,449
Increase (decrease):
Differences required to be flowed-through by regulatory commissions	85			61			1,414			1,494
Other, net	(100		)	(9		)	(1,238		)	(178		)
Income tax expense	$	1,414		$	780		$	20,497		$	27,765
Effective income tax rate	39.2		%	42.1		%	40.0		%	41.6		%