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		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	$ 2,920	$ 1,595	$ 5,393	$ 2,846
Available-for-sale Securities, Gross Realized Losses	(28)	0	(28)	0
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities	(27)	(57)	(27)	(57)
Available-for-sale Securities, Gross Realized Gain (Loss)	2,865	1,538	5,338	2,789
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	1,083	1,517	2,222	2,603
Available-for-sale Securities, Gross Realized Losses	(28)	0	(28)	0
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities	(27)	(57)	(27)	(57)
Available-for-sale Securities, Gross Realized Gain (Loss)	1,028	1,460	2,167	2,546
Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross Realized Gains	1,837	78	3,171	243
Available-for-sale Securities, Gross Realized Losses	0	0	0	0
Other than Temporary Impairment Losses, Investments, Available-for-sale Securities	0	0	0	0
Available-for-sale Securities, Gross Realized Gain (Loss)	$ 1,837	$ 78	$ 3,171	$ 243