Share-Based Payments - Option Rollforward (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning (in shares)	1,160,933
Granted (in shares)	187,000
Expired and canceled (in shares)	(12,440)
Forfeited prior to vesting (in shares)	(38,341)
Exercise of stock options (in shares)	(159,869)
Outstanding, ending (in shares)	1,137,283	1,160,933
Vested and expected to vest (in shares)	1,137,283
Vested (in shares)	853,350
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted average exercise price, outstanding, beginning (in dollars per share)	$ 4.50
Weighted average exercise price, granted (in dollars per share)	$ 4.06
Weighted average exercise price, expired and canceled (in dollars per share)	$ 4.93
Weighted average exercise price, forfeited prior to vesting (in dollars per share)	$ 4.23
Weighted average exercise price, exercised (in dollars per share)	$ 3.07
Weighted average exercise price, outstanding, ending (in dollars per share)	$ 4.63	$ 4.50
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 4.63
Vested, weighted average exercise price (in dollars per share)	$ 4.71
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding, weighted average remaining contractual term (in years)	5 years 5 months 19 days
Vested, weighted average remaining contractual term (in years)	4 years 3 months 3 days
Outstanding, aggregate intrinsic value (in dollars)	$ 256
Vested, aggregate intrinsic value (in dollars)	232
Weighted average grant date fair value, granted (in dollars per share)	$ 2.16	$ 2.85
Intrinsic value of options exercised	$ 152	$ 411