Pension and Post-Retirement Benefit Costs (Tables)

9 Months Ended

Sep. 30, 2012

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Components of Net Periodic Benefit Cost

Components of net periodic benefit cost are as follows:

	Three Months Ended September 30,										Nine Months Ended September 30,
	Pension						Post-retirement Healthcare				Pension						Post-retirement Healthcare
	2012			2011			2012		2011		2012			2011			2012		2011
Service cost	$	250		$	224		$	2	$	4	$	754		$	705		$	7	$	12
Interest cost	645			681			185		209		1,936			2,042			555		628
Expected return on plan assets	(623		)	(570		)	—		—		(1,867		)	(1,709		)	—		—
Amortization of transition    obligation	—			—			—		28		—			—			—		85
Amortization of prior service    cost	74			74			21		47		223			223			63		140
Amortization of net loss	445			322			44		28		1,329			948			132		84
Net periodic benefit cost	$	791		$	731		$	252	$	316	$	2,375		$	2,209		$	757	$	949