Fair Value Measurements (Details 5) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Financial assets:
Non-covered loans, net	$ 3,277,044	$ 3,148,987
Covered loans	1,096,590
Broker-dealer and clearing organization receivables	132,636	145,564
FDIC indemnification asset	190,041
Financial liabilities:
Broker-dealer and clearing organization payables	142,411	187,990
Level 2
Financial assets:
Non-covered loans, net	286,663
Broker-dealer and clearing organization receivables	132,636	145,564
Other assets	51,134	59,094
Financial liabilities:
Deposits	6,936,527	4,698,848
Broker-dealer and clearing organization payables	142,411	187,990
Short-term borrowings	305,297	728,250
Debt	231,416	217,092
Other liabilities	4,651	4,400
Level 3
Financial assets:
Non-covered loans, net	3,018,250	3,148,987
Covered loans	1,096,590
FDIC indemnification asset	190,041
Other assets	17,289
Total Fair Value
Financial assets:
Non-covered loans, net	3,304,913	3,148,987
Covered loans	1,096,590
Broker-dealer and clearing organization receivables	132,636	145,564
FDIC indemnification asset	190,041
Other assets	68,423	59,094
Financial liabilities:
Deposits	6,936,527	4,698,848
Broker-dealer and clearing organization payables	142,411	187,990
Short-term borrowings	305,297	728,250
Debt	231,416	217,092
Other liabilities	4,651	4,400
Carrying Amount
Financial assets:
Non-covered loans, net	3,277,044	3,148,987
Covered loans	1,096,590
Broker-dealer and clearing organization receivables	132,636	145,564
FDIC indemnification asset	190,041
Other assets	68,423	59,094
Financial liabilities:
Deposits	6,936,162	4,700,461
Broker-dealer and clearing organization payables	142,411	187,990
Short-term borrowings	305,297	728,250
Debt	207,123	208,551
Other liabilities	$ 4,651	$ 4,400