Statements of Consolidated Comprehensive Income (Loss) Statements of Consolidated Comprehensive Income (Loss) (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Income and Comprehensive Income (Parenthetical) [Abstract]
Unrealized gain (loss) on available-for-sale security, net of deferred tax of $0, $145, and $4, respectively	$ 0	$ 145	$ 4
Actuarial gain (loss), net of deferred tax of $103,308, $1,903, and $104,425, respectively	103,308	1,903	104,425
Net actuarial loss included in periodic benefit expense or income, net of deferred tax of $7,562, $7,969, and $4,373, respectively	7,562	7,969	4,373
Prior-service cost or credit, net of deferred tax of $7,505, $17,577, and $0, respectively	7,505	17,577	0
Amortization of prior service cost or credit included in net periodic benefit expense or income, net of deferred tax of $552, $465, and $468, respectively	$ 552	$ 465	$ 468