Contingencies And Other Disclosures (Schedule Of Original Purchase Amount Of Investments Subject To Litigation) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 25, 2014
Alternativea Mortgage Loan Pools [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	$ 482,085
Ending balance of the investments at issue			190,088
Alternativea Mortgage Loan Pools [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	0
Ending balance of the investments at issue			0
Alternativea Mortgage Loan Pools [Member] | 2005 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	200,118	[1]
Ending balance of the investments at issue			59,230
Alternativea Mortgage Loan Pools [Member] | 2005 [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	0
Ending balance of the investments at issue			0
Alternativea Mortgage Loan Pools [Member] | 2006 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	77,906	[1]
Ending balance of the investments at issue			36,254
Alternativea Mortgage Loan Pools [Member] | 2006 [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	0
Ending balance of the investments at issue			0
Alternativea Mortgage Loan Pools [Member] | 2007 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	204,061
Ending balance of the investments at issue			94,604
Alternativea Mortgage Loan Pools [Member] | 2007 [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	0
Ending balance of the investments at issue			0
Jumbo Mortgage Loans [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	80,000
Ending balance of the investments at issue			26,625
Jumbo Mortgage Loans [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	16,877
Ending balance of the investments at issue			1,614
Jumbo Mortgage Loans [Member] | 2005 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	30,000
Ending balance of the investments at issue			10,665
Jumbo Mortgage Loans [Member] | 2005 [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	0
Ending balance of the investments at issue			0
Jumbo Mortgage Loans [Member] | 2006 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	0
Ending balance of the investments at issue			0
Jumbo Mortgage Loans [Member] | 2006 [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	9,793
Ending balance of the investments at issue			1,614
Jumbo Mortgage Loans [Member] | 2007 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	50,000
Ending balance of the investments at issue			15,960
Jumbo Mortgage Loans [Member] | 2007 [Member] | Junior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	7,084
Ending balance of the investments at issue			0
Federal Housing Finance Agency [Member] | Alternativea Mortgage Loan Pools [Member] | 2005 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	643,751
Federal Housing Finance Agency [Member] | Alternativea Mortgage Loan Pools [Member] | 2006 [Member] | Senior Investor Rank [Member]
Loss Contingencies [Line Items]
Original purchase amounts of the investments at issue	$ 230,020

[1] Excluded from the amounts shown in the table are certificates which were the subject of the FHFA litigation; $230,020 of Senior Alt-A loans from 2006 and $643,751 of Senior Alt-A loans from 2005. The FHFA litigation was pending at quarter-end but was settled in April 2014.