Fair Value Measurements (Details 1) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Dec. 31, 2011
Available-for-sale Securities [Member]
Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3)
Beginning Balance	$ 856	$ 1,672
Total net gain (losses) included in income:
Net impairment losses on investment securities		(816)
Sale of investment securities	(425)
Total net losses included in other comprehensive income
Investment securities losses	(24)
Ending Balance	407	856
Derivatives [Member]
Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3)
Beginning Balance	(200)	5,539
Total net gain (losses) included in income:
Mortgage derivative gain (loss), net	9,599	(5,739)
Total net losses included in other comprehensive income
Ending Balance	$ 9,399	$ (200)