Stockholders' Equity - Stock Options Outstanding Rollforward (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011 Stock options [Member]	Dec. 31, 2010 Stock options [Member]
Number of Options
Outstanding at December 31, 2011 (in shares)	816,077
Granted (in shares)	496,240
Exercised (in shares)	(80,255)
Expired, canceled or forfeited (in shares)	(154,264)
Outstanding at December 31, 2012 (in shares)	1,077,798
Exercisable at December 31, 2012 (in shares)	290,911	361,994	416,710
Weighted Average Exercise Price
Outstanding at December 31, 2011 (in dollars per share)	$ 11.28
Granted (in dollars per share)	$ 9.91
Exercised (in dollars per share)	$ 8.58
Expired, canceled or forfeited (in dollars per share)	$ 10.72
Outstanding at December 31, 2012 (in dollars per share)	$ 10.93
Exercisable at December 31, 2012 (in dollars per share)	$ 10.52	$ 9.36	$ 10.06
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Stock options, Outstanding, Weighted Average Remaining Contractual Life	3 years 3 months 11 days	2 years 7 months 17 days	2 years 3 months 11 days
Stock options, Exercisable, Weighted Average Remaining Contractual Life	1 year 9 months 11 days	1 year 2 months 5 days	1 year 5 months 8 days
Stock options, Outstanding, Aggregate Intrinsic Value	$ 3,391,000	$ 112,000	$ 1,254,000
Stock options, Exercisable, Aggregate Intrinsic Value	$ 1,032,000	$ 85,000	$ 851,000

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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