Investment Securities Investment Securities Gains, Losses, and Proceeds (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Gross gains			$ 5,251	$ 1,102	$ 1,184
Gross losses			(4,009)	(690)	(690)
Investment securities gains, net	$ 1,242	$ 34	1,242	412	494
Proceeds from sales of investment securities	$ 1,000,000		$ 1,065,328	$ 80,362	$ 102,011