Contingencies And Other Disclosures (Narrative I) (Details) shares in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Oct. 31, 2014 USD ($)	Mar. 31, 2016 USD ($) number shares	Mar. 31, 2015 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2007 USD ($)	Sep. 30, 2014 USD ($)	Mar. 31, 2008 shares
Loss Contingencies [Line Items]
Estimated Litigation Liability		$ 14,400,000
Number of GSEs to which conventional conforming single-family mortgage loans were predominately sold to | number		2
Percent Of Repurchase Make Whole Claims Related To Private Whole Loan Sales				90.00%
Loan-to-value ratio at origination		80.00%
Accrued losses on loan repurchase exposure		$ 115,000,000	$ 117,100,000
Litigation And Regulatory Matters		(475,000)	162,500,000
Mortgage loans originated and sold to agencies				$ 69,500,000,000
Loans sold to GSEs				57,600,000,000
Loans Guaranteed By Ginnie Mae				$ 11,900,000,000
Loans included in FH proprietary securitizations					$ 26,700,000,000
Fha Insured [Member]
Loss Contingencies [Line Items]
Amount Of Insurance Recoveries Company Is Pursuing		75,000,000
Litigation Settlement Expense		212,500,000
Mortgage Securitization Litigation [Member]
Loss Contingencies [Line Items]
Investment in proprietary securitizations subject to lawsuits		145,700,000
Investment in proprietary securitizations subject to indemnifications		$ 510,100,000
Visa Class B Shares [Member]
Loss Contingencies [Line Items]
Number of Visa Class B shares | shares		1.1					2.4
Additional amount deposited into escrow account by Visa						$ 450,000,000
Cash payment to counterparty	$ 2,400,000
Estimated conversion ratio		165.00%
Contingent liability		$ 800,000
Derivative liability		4,600,000	$ 5,000,000
Historical cost		0
Subservicer expenditure reimbursement amount disputed
Loss Contingencies [Line Items]
Actual damages sought by plaintiff		43,500,000
Minimum
Loss Contingencies [Line Items]
Estimated reasonably possible losses in excess of currently established liabilities		0
Minimum | Debit Transaction Sequencing Matter [Member]
Loss Contingencies [Line Items]
Actual damages sought by plaintiff		5,000,000
Maximum
Loss Contingencies [Line Items]
Estimated reasonably possible losses in excess of currently established liabilities		$ 108,000,000