Quarterly report pursuant to Section 13 or 15(d)

Loans sales and securitizations (Details)

Loans sales and securitizations (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2012
Mar. 31, 2011
Summarize the changes in MSRs using the fair value method    
Fair value, beginning of period $ 65,001 $ 125,679
Change in fair value during the period due to:    
Time decay (856) [1] (1,374) [1]
Payoffs (4,039) [2] (5,872) [2]
Changes in valuation inputs or assumptions 2,348 [3] 774 [3]
Fair value, end of period 62,454 119,207
Residential Mortgage [Member]
Summarizes activity relating to residential mortgage loans sold with servicing retained    
Residential mortgage loans sold with servicing retained 1,006,084 1,257,503
Pretax gains resulting from above loan sales $ 28,941 [4] $ 32,679 [4]
[1] Represents decrease in value due to passage of time, including the impact from both regularly scheduled loan principal payments and partial loan paydowns.
[2] Represents decrease in value associated with loans that paid off during the period.
[3] Represents change in value resulting primarily from market-driven changes in interest rates and prepayment spreads.
[4] Recorded in other noninterest income.