Accumulated Other Comprehensive Income (Loss) - Reclassification (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Realized gain (loss)			$ (3,245)
Total before tax	9,849		(4,425)
Tax benefit (expense)	(2,873)		2,839
Income (loss) from continuing operations	6,976		(1,586)
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Realized gain (loss)			(2,723)
Tax benefit (expense)			1,555
Income (loss) from continuing operations			(1,168)
Accumulated Defined Benefit Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Prior service costs	(35)	[1]	(3)	[1]
Actuarial losses	(1,559)	[1]	(1,464)	[1]
Total before tax	(1,594)		(1,467)
Tax benefit (expense)	557		0
Income (loss) from continuing operations	$ (1,037)		$ (1,467)

[1] These accumulated other comprehensive income components are included in the computation of net periodic pension cost. See Note 8 - "Pension benefit and other post-retirement benefit plans" for additional details.