Derivative Instruments and Hedging Activities (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended			3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Jul. 28, 2010 Related Interest Rate Swaps [Member] Total Return Swap [Member]	Sep. 30, 2010 Total Return Swap [Member]	Jun. 30, 2011 Total Return Swap [Member]	Dec. 31, 2010 Total Return Swap [Member]
Derivative Assets	$ 3,200,000	$ 5,300,000	$ 3,200,000	$ 5,300,000
Derivative, Net Liability Position, Aggregate Fair Value	(400,000)	(400,000)	(400,000)	(400,000)
Cash collateral used to reduce amounts of derivative assets	0	1,500,000	0	1,500,000
Cash collateral used to reduce amounts of derivative liabilities	2,400,000	1,800,000	2,400,000	1,800,000
Total projected gains and accretion/amortization in AOCI to be reclassified as interest income, total			21,000,000
Interest rate swap, credit risk rate			20.00%
Notional amount					1,160,000,000
Negative initial value	4,195,000	(1,552,000)	5,415,000	636,000		22,800,000
Total net gains (losses) included in, Other noninterest expense	72,773,000	62,958,000	139,524,000	117,790,000		11,600,000
Fair value of the TRS derivative liability							5,400,000	15,900,000
Net quarterly costs							$ 5,300,000