Income Taxes - Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Assets
Deferred compensation	$ 8,065	$ 6,671
Loss carryforwards	1,094	1,120
Accruals deductible for tax purposes when paid	457	412
Depreciation	57	358
Allowance for doubtful accounts	289	316
Amortization	0	84
State taxes	792	811
Gross deferred tax assets	10,754	9,772
Deferred tax asset valuation allowance	(2,269)	(1,404)	(2,693)	(2,649)
Gross deferred tax assets less valuation allowance	8,485	8,368	7,261
Liabilities [Abstract]
Depreciation	(820)	(77)
Other	(85)	(8)
Gross deferred tax liabilities	(905)	(85)
Net deferred tax assets	7,580	8,283
Net deferred tax assets and liabilities are recorded as follows:	1,145	1,221
Net non-current assets	$ 6,435	$ 7,062