Statement of Comprehensive Income Other Comprehensive Income, Deferred Tax (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Other Comprehensive Income, Deferred Tax [Abstract]
Net actuarial loss included in net periodic benefit expense or income, tax	$ 794	$ 1,922
Amortization of prior service cost or credit included in net periodic benefit expense or income, tax	$ 122	$ 61