Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Gross Realized Gains	$ 9,067	$ 2,393	$ 8,178
Gross Realized Losses	(1)	(322)	(50)
Other- than- temporary Impairment Losses	0	(30)	(124)
Net Gains	9,066	2,041	8,004
Equity securities
Gross Realized Gains	6,496	335	4,391
Gross Realized Losses	(1)	0	(28)
Other- than- temporary Impairment Losses	0	(12)	(27)
Net Gains	6,495	323	4,336
Debt securities
Gross Realized Gains	2,571	2,058	3,787
Gross Realized Losses	0	(322)	(22)
Other- than- temporary Impairment Losses	0	(18)	(97)
Net Gains	$ 2,571	$ 1,718	$ 3,668