Investment Securities (Pooled Trust Preferred Securities) (Details) (USD $) In Thousands, unless otherwise specified				6 Months Ended												3 Months Ended		3 Months Ended																6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Jun. 30, 2012 TROPC 2003-1A [Member]	Jun. 30, 2012 MM Community Funding IX [Member]	Jun. 30, 2012 Reg Div Funding 2004 [Member]	Jun. 30, 2012 Pretsl XII [Member]	Jun. 30, 2012 Pretsl XV [Member]	Jun. 30, 2012 Reg Div Funding 2005 [Member]	Jun. 30, 2012 Pretsl XXVII LTD [Member]	Jun. 30, 2012 Trapeza Ser 13A [Member]	Jun. 30, 2012 First Empire Cap (M&T) 1 [Member]		Jun. 30, 2012 First Empire Cap (M&T) 2 [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member]	Dec. 31, 2011 Pooled Trust Preferred Securities [Member]	Jun. 30, 2012 Pooled Trust Preferred Securities [Member] TROPC 2003-1A [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] MM Community Funding IX [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] Reg Div Funding 2004 [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] Pretsl XII [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] Pretsl XV [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] Reg Div Funding 2005 [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] Pretsl XXVII LTD [Member]		Jun. 30, 2012 Pooled Trust Preferred Securities [Member] Trapeza Ser 13A [Member]		Jun. 30, 2012 Single Issuer Trust Preferred Securities [Member]	Jun. 30, 2012 Single Issuer Trust Preferred Securities [Member] Fleet Cap Tr V (BOA) [Member]		Jun. 30, 2012 Single Issuer Trust Preferred Securities [Member] JP Morgan Chase Cap XIII [Member]		Jun. 30, 2012 Trust Preferred Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Pooled trust preferred securities, Class																		A4L		B-2		B-2		B-1		B-1		B-1		B		A2A
Lowest Credit Rating												BB+	[1]	BB+	[1]			C	[1]	D	[1]	D	[1]	C	[1]	C	[1]	C	[1]	CC	[1]	B	[1]		BB	[1]	BBB	[1]
Amortized Cost	$ 2,155,885	$ 2,030,801										$ 956		$ 2,907		$ 25,294	$ 25,461	$ 86		$ 2,067		$ 4,017		$ 2,843		$ 1,695		$ 311		$ 4,877		$ 9,398		$ 11,943	$ 3,362		$ 4,718		$ 37,237
Pooled trust preferred securities, Fair Value	2,208,262	2,071,276	2,202,855									1,054		3,161		8,460	7,327	22		858		475		1,385		1,115		27		1,068		3,510		10,806	2,816		3,775		19,266
Available-for-sale, Unrealized Losses	(22,682)	(25,592)										98		254		(16,834)	(18,134)	(64)		(1,209)		(3,542)		(1,458)		(580)		(284)		(3,809)		(5,888)		(1,137)	(546)		(943)		(17,971)
Realized Losses 2012												$ 0		$ 0		$ 161		$ 0		$ 0		$ 161		$ 0		$ 0		$ 0		$ 0		$ 0		$ 0	$ 0		$ 0		$ 161
# of Issuers Currently Performing				14	16	24	49	49	18	33	43
# of Issuers Currently Remaining				36	31	45	74	71	48	49	54
Actual Deferrals and Defaults as a Percent of Original Collateral																		45.20%		41.10%		45.70%		27.90%		32.60%		55.90%		28.10%		29.00%
Expected Defaults as a % of Remaining Performing Collateral																		15.90%		8.30%		6.30%		8.00%		6.30%		30.20%		24.90%		19.40%
Excess Subordination as a % of Current Performing Collateral																		0.00%		0.00%		0.00%		0.00%		0.00%		0.00%		28.50%		39.60%

[1] Lowest rating for the security provided by any nationally recognized credit rating agency.