Loans and leases and the allowance for credit losses (Details 5) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Interest income recognized on loans
Average Recorded Investment	$ 1,148,537	$ 1,042,197	$ 1,144,988	$ 1,142,760
Interest Income Recognized, Total	6,727	5,895	19,271	16,359
Interest Income Recognized, Cash Basis	3,567	2,673	9,510	7,468
Commercial, financial, leasing, etc. [Member]
Interest income recognized on loans
Average Recorded Investment	152,368	219,225	163,005	262,310
Interest Income Recognized, Total	1,172	334	2,844	1,509
Interest Income Recognized, Cash Basis	1,166	326	2,820	1,492
Commercial real estate loans [Member]
Interest income recognized on loans
Average Recorded Investment	195,832	167,462	191,818	219,816
Interest Income Recognized, Total	810	1,089	1,705	1,585
Interest Income Recognized, Cash Basis	808	949	1,630	1,426
Residential builder and developer [Member]
Interest income recognized on loans
Average Recorded Investment	338,897	268,579	321,386	282,762
Interest Income Recognized, Total	422	352	1,261	1,058
Interest Income Recognized, Cash Basis	98	72	338	513
Other commercial construction [Member]
Interest income recognized on loans
Average Recorded Investment	96,482	26,550	102,978	28,342
Interest Income Recognized, Total	62	79	759	368
Interest Income Recognized, Cash Basis	51	65	522	354
Residential real estate excluding Alt-A [Member]
Interest income recognized on loans
Average Recorded Investment	98,885	70,418	92,918	58,120
Interest Income Recognized, Total	1,183	774	3,209	1,985
Interest Income Recognized, Cash Basis	630	477	1,770	1,256
Residential Alt-A [Member]
Interest income recognized on loans
Average Recorded Investment	192,609	219,778	199,066	223,328
Interest Income Recognized, Total	1,872	2,082	5,858	6,410
Interest Income Recognized, Cash Basis	494	453	1,455	1,338
Home equity lines and loans [Member]
Interest income recognized on loans
Average Recorded Investment	11,814	11,128	11,989	11,809
Interest Income Recognized, Total	174	177	523	536
Interest Income Recognized, Cash Basis	26	26	74	88
Automobile [Member]
Interest income recognized on loans
Average Recorded Investment	56,071	55,871	57,704	53,062
Interest Income Recognized, Total	957	951	2,925	2,722
Interest Income Recognized, Cash Basis	262	293	850	959
Other [Member]
Interest income recognized on loans
Average Recorded Investment	5,579	3,186	4,124	3,211
Interest Income Recognized, Total	75	57	187	186
Interest Income Recognized, Cash Basis	$ 32	$ 12	$ 51	$ 42