Borrowings (Retail Repurchase Agreements And Other Short Term Borrowings) (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
Retail repurchase agreements carrying amount	$ 74,432,000	$ 53,842,000	$ 51,929,000
Retail repurchase agreements average	70,097,000	55,769,000	63,864,000
Retail repurchase agreements maximum	$ 82,702,000	$ 59,410,000	$ 73,130,000
Retail Repurchase Agreements Interest Rate	0.24%	0.20%	0.20%
Retail Repurchase Agreements Average Interest Rate	0.23%	0.26%	0.28%