Securities (Securities Pooled Trust Preferred Unrealized Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$ 380,994			$ 380,994			$ 363,408
Securities available for sale	388,085			388,085			375,498
Available for sale debt securities fair value	388,085			388,085
Available for sale securities unrealized losses	(6,821)			(6,821)			(9,119)
Additional increases to the amount of credit-related impairment loss on debt securities for which other-than-temporary impairment was previously recognized	0		0	2,772		209
Trust preferred securities: Collateralized debt obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities amortized cost	1,264			1,264			4,036
Available for sale debt securities fair value	425			425			843
Available for sale securities unrealized losses	(839)			(839)			(3,193)
Nonaccrual Investment Security [Member] | Trust preferred securities: Collateralized debt obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available for sale debt securities amortized cost	1,264	[1]		1,264	[1]		4,036	[1]
Available for sale debt securities fair value	425			425			843
Available for sale securities unrealized losses	(839)			(839)			(3,193)
Tropic CDO1, tranche A4L [Member] | Nonaccrual Investment Security [Member] | Trust preferred securities: Collateralized debt obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	0	[1]		0	[1]		2,772	[1]
Securities available for sale	0			0			613
Available for sale securities unrealized losses	0			0			(2,159)
Additional increases to the amount of credit-related impairment loss on debt securities for which other-than-temporary impairment was previously recognized				2,800
Preferred Term Security [PreTSL] XXV, tranche C1 [Member] | Nonaccrual Investment Security [Member] | Trust preferred securities: Collateralized debt obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	1,264	[1]		1,264	[1]		1,264	[1]
Securities available for sale	425			425			230
Available for sale securities unrealized losses	$ (839)			$ (839)			$ (1,034)

[1] Net of other-than-temporary impairment losses recognized in earnings.