Fair Values of Financial Instruments (Reconciliation of Recurring Fair Value Measurements Recognized in Balance Sheet using Significant Unobservable (Level Three) Inputs) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Values of Financial Instruments [Abstract]
Beginning balance	$ 3,336	$ 2,475	$ 2,454
Total realized and unrealized gains (losses)
Included in net income	(68)
Included in other comprehensive income (loss)	2,098	897	30
Sales	(2,826)
Settlements	(18)	(36)	(9)
Ending balance	2,522	3,336	2,475
Total gains or losses for the period included in net income attributable to the change in unrealized gains or losses related to assets still held at the reporting date	$ 0	$ 0	$ 0