Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	$ 85	$ 146	$ 2,931	$ 3,799
Gross Realized Losses	0	0	0	(19)
Other-than-temporary Impairment Losses	(43)	(589)	(100)	(2,273)
Net Gains (Losses)	42	(443)	2,831	1,507
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	0	146	2,603	194
Gross Realized Losses	0	0	0	0
Other-than-temporary Impairment Losses	(24)	(244)	(81)	(575)
Net Gains (Losses)	(24)	(98)	2,522	(381)
Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	85	0	328	3,605
Gross Realized Losses	0	0	0	(19)
Other-than-temporary Impairment Losses	(19)	(345)	(19)	(1,698)
Net Gains (Losses)	$ 66	$ (345)	$ 309	$ 1,888