Loans (Narrative) (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2012 number Y		Jun. 30, 2011		Jun. 30, 2012 number Y		Jun. 30, 2011		Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 321,051,000	[1],[2]	$ 524,091,000	[1],[2]	$ 321,051,000	[1],[2]	$ 524,091,000	[1],[2]	$ 346,016,000	$ 384,351,000	$ 589,128,000	$ 664,799,000
Average balance of impaired loans	493,895,000		610,449,000		489,837,000		612,203,000
Interest income recognized on impaired loan	1,820,000		1,793,000		3,526,000		3,118,000
All commercial loans					1,000,000
Certain commercial loans that are graded 13 or worse					500,000
Forbearance agreements time period	generally 3 to 6 months				generally 3 to 6 months
Consumer TDR, reduction of interest rate by increment, basis points	25				25
Modified interest rate, minimum consumer loan	1.00%				1.00%
Modified interest rate time period, maximum for consumer loans	5				5
Permanent Mortgage Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	29,112,000	[2]	46,602,000	[2]	29,112,000	[2]	46,602,000	[2]	32,572,000	26,194,000	55,640,000	65,009,000
Maximum maturities in years for TDRS	40				40
Loans Held-For-Sale [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings loans	139,300,000		70,100,000		139,300,000		70,100,000
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk, percentage	41.00%				41.00%
Consumer Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk, percentage	33.00%				33.00%
Allowance for loan losses	133,421,000	[1]	162,655,000	[1]	133,421,000	[1]	162,655,000	[1]	141,647,000	165,077,000	179,394,000	192,350,000
Maximum maturities in years for TDRS	30				30
Bank-Related And TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage contributed in total loan	4.00%				4.00%
Percentage of commercial loan portfolio	7.00%				7.00%
Bank-related and trust preferred loans total	600,000,000				600,000,000
Modified Loans Classified As A TDR [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings loans	338,800,000		306,200,000		338,800,000		306,200,000
Allowance for loan losses	64,400,000		45,200,000		64,400,000		45,200,000
Ratio of the allowance for loan losses to loans	19.00%		15.00%		19.00%		15.00%
Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage contributed in total loan	8.00%				8.00%
Percentage of commercial loan portfolio	16.00%				16.00%
All commercial loans					1,300,000,000
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Payment reductions, time period	1				1
Credit card workout program, maximum, term extension (in years)	5				5
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impaired nonaccrual commercial loans, minimum					$ 1,000,000
Payment reductions, time period	6				6
Credit card workout program, granted rate reduction, percentage, minimum	0.00%				0.00%

[1] Balances as of June 30, 2012 and 2011 include $19.0 million and $29.9 million of reserves, respectively, and $447.5 million and $649.2 million of balances in restricted consumer real estate loans and secured borrowings, respectively.

[2] Balances as of June 30, 2012 and 2011 include $1.3 million and $3.1 million of reserves, respectively, and $16.9 million and $44.9 million of balances in restricted permanent mortgage loans and secured borrowings, respectively.