Shareholders' Equity (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2006	Dec. 31, 2007	Dec. 31, 2017
Dividends:
Amount of additional dividends the bank could have declared			$ 209.8
Reserved Shares:
Reserved shares available for grant			1,989,991
2006 Stock Repurchase Plan [Member]
Stock Repurchase Program:
Authorized amount (in shares)	400,000
Authorized amount as a percentage of total common stock	3.00%
Cumulative amount of shares purchased			185,400
Shares repurchased, value		$ 4.8