Components of Net Periodic Benefit Cost (Tables)

9 Months Ended

Sep. 30, 2013

Compensation and Retirement Disclosure [Abstract]

Schedule of Net Benefit Costs

	Three Months Ended September 30,										Nine Months Ended September 30,
	(000's)										(000's)
	Pension Benefits						Post-Retirement Health Benefits				Pension Benefits						Post-Retirement Health Benefits
	2013			2012			2013		2012		2013			2012			2013		2012
Service cost	$	559		$	1,218		$	17	$	15	$	1,678		$	3,654		$	51	$	82
Interest cost	846			917			43		43		2,537			2,750			130		180
Expected return on plan assets	(827		)	(815		)	—		—		(2,482		)	(2,444		)	—		—
Amortization of transition obligation	—			—			15		15		—			—			44		45
Net amortization of prior service cost	(4		)	41			—		—		(12		)	124			—		—
Net amortization of net (gain) loss	523			567			—		—		1,568			1,702			—		—
Net Periodic Benefit Cost	$	1,097		$	1,928		$	75	$	73	$	3,289		$	5,786		$	225	$	307