Reserve for Unfunded Commitments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Summary of the activity in reserve for unfunded commitments
Balance at beginning of period	$ 3,615	$ 2,740
Provision for losses - unfunded commitments	(440)	(190)
Balance at end of period	$ 3,175	$ 2,550