Investment Securities (Schedule of Pooled Trust Preferred Securities) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012		Sep. 30, 2011	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Book value	$ 416,738		$ 416,738			$ 341,023
Fair value	425,215		425,215			348,091
Realized OTTI credit loss (YTD 2012)	0	97	0		97
Total other-than-temporary impairment loss on investment securities	0	(97)	0		(97)
PreTSL IV [Member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine*	[1]
Book value	243		243
Fair value	201		201
Unrealized gains(losses)			(42)
Total other-than-temporary impairment loss on investment securities			(1)
Moody's/ Fitch ratings			Caa2/CCC
Current number of performing banks	4		4
Current number of performing insurance companies	-		-
Actual deferrals and defaults as a % of total collateral			27.10%
Total performing collateral as a % of outstanding bonds			124.70%
PreTSL V [Member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine*	[1]
Total other-than-temporary impairment loss on investment securities			(118)
Moody's/ Fitch ratings			C/D
Current number of performing banks	-		-
Current number of performing insurance companies	-		-
Actual deferrals and defaults as a % of total collateral			100.00%
Total performing collateral as a % of outstanding bonds			12.20%
PreTSL VI [member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine*	[1]
Total other-than-temporary impairment loss on investment securities			(8)
PreTSl XVII [member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine
Book value	752		752
Fair value	369		369
Unrealized gains(losses)			(383)
Total other-than-temporary impairment loss on investment securities			(222)
Moody's/ Fitch ratings			C/C
Current number of performing banks	29		29
Current number of performing insurance companies	4		4
Actual deferrals and defaults as a % of total collateral			41.80%
Total performing collateral as a % of outstanding bonds			70.80%
PreTSL XIX [member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine
Book value	988		988
Fair value	442		442
Unrealized gains(losses)			(546)
Moody's/ Fitch ratings			C/C
Current number of performing banks	33		33
Current number of performing insurance companies	13		13
Actual deferrals and defaults as a % of total collateral			28.20%
Total performing collateral as a % of outstanding bonds			76.00%
PreTSL XXV [Member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine
Book value	766		766
Fair value	362		362
Unrealized gains(losses)			(404)
Total other-than-temporary impairment loss on investment securities			(222)
Moody's/ Fitch ratings			C/C
Current number of performing banks	42		42
Current number of performing insurance companies	6		6
Actual deferrals and defaults as a % of total collateral			34.30%
Total performing collateral as a % of outstanding bonds			77.10%
PreTSL XXVI [Member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine
Book value	469		469
Fair value	248		248
Unrealized gains(losses)			(221)
Total other-than-temporary impairment loss on investment securities			(270)
Moody's/ Fitch ratings			C/C
Current number of performing banks	39		39
Current number of performing insurance companies	8		8
Actual deferrals and defaults as a % of total collateral			29.50%
Total performing collateral as a % of outstanding bonds			82.60%
PreTSL XXVI [member]
Schedule of Available-for-sale Securities [Line Items]
Class			Mezzanine
Book value	301		301
Fair value	339		339
Unrealized gains(losses)			38
Total other-than-temporary impairment loss on investment securities			(438)
Moody's/ Fitch ratings			C/C
Current number of performing banks	39		39
Current number of performing insurance companies	8		8
Actual deferrals and defaults as a % of total collateral			29.50%
Total performing collateral as a % of outstanding bonds			82.60%
Pooled trust preferred securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Book value	3,519		3,519			3,640
Fair value	1,961		1,961			1,929
Unrealized gains(losses)			(1,558)
Total other-than-temporary impairment loss on investment securities			$ (1,279)

[1] Mezzanine* - only class of bonds still outstanding (represents the senior-most obligation of the trust)