Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Fair Value Measurements
Transfers of assets from level 1 to level 2	$ 0	$ 0	$ 0	$ 0
Transfers of assets from level 2 to level 1	0	0	0	0
Transfers of liabilities from level 1 to level 2	0	0	0	0
Transfers of liabilities from level 2 to level 1	0	0	0	0
Changes in Fair Value for Assets and Liabilities Reported at Fair Value under Fair Value Option
Net Gains from Sale of Loans	105,337		375,464
Other Noninterest Income	11,625	1,895	28,385	5,457
Loans held for sale
Changes in Fair Value for Assets and Liabilities Reported at Fair Value under Fair Value Option
Net Gains from Sale of Loans	44,395		2,754
Total Changes in Fair Value	44,395		2,754
Mortgage servicing asset
Changes in Fair Value for Assets and Liabilities Reported at Fair Value under Fair Value Option
Net Gains from Sale of Loans	6,290		11,321
Total Changes in Fair Value	6,290		11,321
Time deposits
Changes in Fair Value for Assets and Liabilities Reported at Fair Value under Fair Value Option
Other Noninterest Income			12
Total Changes in Fair Value			$ 12

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Represents the total of noninterest income derived from certain activities and assets including (for example): (1) venture capital investments; (2) bank owned life insurance; (3) foreign currency transactions; and (4) mortgage servicing rights.

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