Share-Based Compensation (Details) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 number	Mar. 31, 2011
Share based compensation expense [Line Items]
Total share-based compensation expense	$ 3,545,000	$ 3,184,000
Cash proceeds received from stock option excercises	0
Stock Option Expense	1,000,000	1,000,000
Unrecognized compensation expense [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value	1,000,000
Restricted Stock Expense	2,000,000	2,000,000
Share Based Compensation Arrangment Roll Forward [Abstract]
Outstanding Beginning Shares	3,587
Granted Shares	12
Exercised Shares	(62)
Forfeited or Expired Shares	0
Outstanding Ending Shares	3,537
Shares Exercisable	2,560
Outstanding Beginning Weighted Average Exercise Price	$ 16.69
Granted Weighted Average Exercise Price	$ 21.83
Exercisable Weighted Average Exercise Price	$ 7.51
Forfeited or Expired Weighted Average Exercise Price	$ 0
Outstanding Ending Weighted Average Exercise Price	$ 16.86
Exercisable Weighted Average Exercise Price	$ 14.69
Outstanding Beginning Weighted Average Exercise Term	5
Outstanding Ending Weighted Average Exercise Term	5
Exercisable Weighted Average Exercise Term	4
Outstanding Beginning Intrinsic Value	22,299,000
Exercised Intrinsic Value	1,066,000
Outstanding Ending Intrinsic Value	26,218,000
Exercisable Intrinsic Value	23,111,000
Stock Options [Member]
Unrecognized compensation expense [Line Items]
Unrecognized share-based compensation expense	9,000,000
Unrecognized share-based compensaion expense - years	2
Restricted Stock [Member]
Unrecognized compensation expense [Line Items]
Unrecognized share-based compensation expense	20,000,000
Unrecognized share-based compensaion expense - years	3
Cost of Sales [Member]
Share based compensation expense [Line Items]
Total share-based compensation expense	103,000	86,000
Selling and Adminstrative Expense [Member]
Share based compensation expense [Line Items]
Total share-based compensation expense	3,126,000	2,868,000
Research and Development Expense [Member]
Share based compensation expense [Line Items]
Total share-based compensation expense	$ 316,000	$ 230,000