Investment Securities (State And Municipal Obligations, By State And Economic Sector) (Details)	6 Months Ended
	Jun. 30, 2014 Y
Sector Classification, Texas [Member]
Investment [Line Items]
% of Portfolio	10.60%
Average Life (in years)	4.5
Average Rating (Moody's)	Aa1
Sector Classification, Florida [Member]
Investment [Line Items]
% of Portfolio	8.90%
Average Life (in years)	4.4
Average Rating (Moody's)	Aa3
Sector Classification New York [Member]
Investment [Line Items]
% of Portfolio	7.50%
Average Life (in years)	6.9
Average Rating (Moody's)	Aa2
Sector Classification, Washington [Member]
Investment [Line Items]
% of Portfolio	5.80%
Average Life (in years)	5.7
Average Rating (Moody's)	Aa2
Sector Classification Ohio [Member]
Investment [Line Items]
% of Portfolio	5.70%
Average Life (in years)	5.0
Average Rating (Moody's)	Aa2
Sector Classification, General Obligation [Member]
Investment [Line Items]
% of Portfolio	34.90%
Average Life (in years)	5.2
Average Rating (Moody's)	Aa2
Sector Classification, Lease [Member]
Investment [Line Items]
% of Portfolio	15.40%
Average Life (in years)	4.8
Average Rating (Moody's)	Aa3
Sector Classification, Housing [Member]
Investment [Line Items]
% of Portfolio	13.70%
Average Life (in years)	4.3
Average Rating (Moody's)	Aa1
Sector Classification, Transportation [Member]
Investment [Line Items]
% of Portfolio	12.70%
Average Life (in years)	4.7
Average Rating (Moody's)	A1
Sector Classification, Limited Tax [Member]
Investment [Line Items]
% of Portfolio	7.50%
Average Life (in years)	6.4
Average Rating (Moody's)	Aa2