Goodwill And Other Intangible Assets (Summary of Finite-Lived Intangible Assets) (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Indefinite-lived Intangible Assets [Line Items]
Total other intangible assets, net	$ 19,510	$ 20,947	$ 22,101
Wealth Management [Member]
Indefinite-lived Intangible Assets [Line Items]
Total other intangible assets, net	19,510	20,947	22,101
Customer Lists [Member] | Specialty Finance [Member]
Indefinite-lived Intangible Assets [Line Items]
Gross carrying amount	1,800	1,800	1,800
Accumulated amortization	(688)	(645)	(510)
Net carrying amount	1,112	1,155	1,290
Core Deposits [Member] | Community Banking [Member]
Indefinite-lived Intangible Assets [Line Items]
Gross carrying amount	37,860	38,176	36,053
Accumulated amortization	(26,127)	(25,159)	(22,347)
Net carrying amount	11,733	13,017	13,706
Customer List And Other Intangibles [Member] | Wealth Management [Member]
Indefinite-lived Intangible Assets [Line Items]
Gross carrying amount	7,390	7,390	7,390
Accumulated amortization	(725)	(615)	(285)
Net carrying amount	$ 6,665	$ 6,775	$ 7,105