Fair Value Measurement (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Loans held for sale	$ 255,201	$ 144,808
Mortgage servicing rights	48,152	63,909	63,753
Fair Value, Measurements, Nonrecurring [Member]
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Impaired loans	146,625	279,179
Mortgage servicing rights	48,152	63,909
Loans held for sale	249,195	144,808
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 1
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Impaired loans	0	0
Mortgage servicing rights	0	0
Loans held for sale	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Impaired loans	146,625	279,179
Mortgage servicing rights	0	0
Loans held for sale	249,195	144,808
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3
Assets and Liabilities Measured at Fair Value on a Non-recurring Basis
Impaired loans	0	0
Mortgage servicing rights	48,152	63,909
Loans held for sale	$ 0	$ 0

Amortized carrying amount (balance) as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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+ Details