Consolidated Statements of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Consolidated Statements of Comprehensive Income
Net unrealized gains on securities arising during the period, taxes	$ 721	$ 2,755	$ 572	$ 2,341
Less: reclassification adjustment to net realized gains, taxes	53	2	53	2
Net unrealized holding gains (losses) arising during the period, taxes		3		9
Less: reclassification adjustment to net income, tax benefits	38	38	75	41
Less: amortization of net loss, prior service gain and transition obligation included in net periodic benefit cost, tax benefits	2,405	1,477	4,878	2,108
Less: reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, taxes	$ 2,095	$ 1,370	$ 4,257	$ 2,801