Other Assets (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Nonmarketable investment securities	$ 2,874		$ 2,866
Insurance premiums receivable	563		876
Accrued interest receivable	3,644		3,933
Income taxes receivable	2,711		719
Deferred income taxes	8,113		9,036
Interest rate caps	68	[1]	250	[1]
Prepaid expenses	3,060		3,641
Other assets	6,010		5,399
Total	$ 27,043		$ 26,720

[1] See Note 9 for further discussion.