Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Total realized/unrealized gains (losses):
Paydowns received on Level 3 assets measured on a recurring basis	$ 4,000	$ 2,100
Securities Available-for-Sale
Level 3 Assets Measured on a Recurring Basis
Balance, beginning of period	19,583	20,982
Total realized/unrealized gains (losses):
Included in other comprehensive income	2,332	651
Settlements	(4,004)	(2,051)
Transfers into level 3	47,165
Other (1)	111	1
Balance, end of period	$ 65,187	$ 19,583