Investments (Narrative) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($) security	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) security	Jun. 30, 2014 USD ($)	Dec. 31, 2014 security
Investments [Abstract]
Gross gains on investments	$ 5,000	$ 42	$ 5,900	$ 300
Gross losses on investments	25	52	53	100
Proceeds from sale of investment securities	$ 15,200	$ 3,000	$ 16,800	$ 14,300
Number of debt security positions | security	23		23		24