Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Statement of Other Comprehensive Income [Abstract]
Net unrealized gain (loss) on cash flow hedges, tax	$ 41		$ 21		$ 615		$ 374
Net unrealized loss on investment securities, tax	(142)		377		(2,984)		618
Amortization of pension and postretirement costs, tax	$ 4,347	[1],[2]	$ 6,404	[1],[2]	$ 15,613	[1],[2]	$ 20,371	[1],[2]

[1] These items are included in the computation of net periodic costs of defined benefit pension plans and nonpension postretirement benefit plans (see Note 15 for additional details).

[2] Amounts in parentheses indicate debits (reductions) to income.