STOCKHOLDERS' EQUITY (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in cash flows from financing activities , excess tax benefits related to stock compensation	$ 2,894	$ 4,230	$ 2,289
Number of share-based compensation plans		1
Weighted average grant date fair value [Abstract]
Share-based compensation expense expected to be recognized over the next fiscal year	4,000
Stock splits and repurchase of common stock
Stock split conversion ratio	Three-for-two
Number of shares authorized to be repurchased (in shares)	3,763,038
Number of shares acquired under stock repurchase plan (in shares)	2,010,488
Number of shares acquired under the stock repurchase plan and subsequently reissued (in shares)	19,545
Treasury stock acquired, average cost (in dollars per share)	$ 5.55
Number of shares related to the repurchase of forfeited restricted shares	16,830
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Impact of compensation cost on net earnings	(2,340)	(2,449)	(1,963)
Stock options outstanding by price range [Abstract]
Shares outstanding (in shares)	2,514,000
Weighted average remaining contractual term of options outstanding (in years)	5.5
Weighted average exercise price of options outstanding (in dollars per share)	$ 14.68
Number of options exercisable (in shares)	2,157,000
Weighted average exercise price of options exercisable (in dollars per share)	$ 12.35
Exercise Price $4.51 - $17.28 [Member]
Stock options outstanding by price range [Abstract]
Range of exercise prices, minimum (in dollars per share)	$ 4.51
Range of exercise prices, maximum (in dollars per share)	$ 17.28
Shares outstanding (in shares)	1,915,000
Weighted average remaining contractual term of options outstanding (in years)	4.6
Weighted average exercise price of options outstanding (in dollars per share)	$ 10.90
Number of options exercisable (in shares)	1,915,000
Weighted average exercise price of options exercisable (in dollars per share)	$ 10.90
Exercise Price $21.39 - $32.21 [Member]
Stock options outstanding by price range [Abstract]
Range of exercise prices, minimum (in dollars per share)	$ 21.39
Range of exercise prices, maximum (in dollars per share)	$ 32.21
Shares outstanding (in shares)	584,000
Weighted average remaining contractual term of options outstanding (in years)	8.4
Weighted average exercise price of options outstanding (in dollars per share)	$ 26.39
Number of options exercisable (in shares)	242,000
Weighted average exercise price of options exercisable (in dollars per share)	$ 23.81
Exercise Price $33.81 - $45.09 [Member]
Stock options outstanding by price range [Abstract]
Range of exercise prices, minimum (in dollars per share)	$ 33.81
Range of exercise prices, maximum (in dollars per share)	$ 45.09
Shares outstanding (in shares)	15,000
Weighted average remaining contractual term of options outstanding (in years)	9.4
Weighted average exercise price of options outstanding (in dollars per share)	$ 40.59
Number of options exercisable (in shares)	0
Weighted average exercise price of options exercisable (in dollars per share)	$ 0
Cost of Sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Impact of compensation cost on earnings component	582	508	365
Operating Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Impact of compensation cost on earnings component	3,110	3,484	2,711
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future awards (in shares)	4,784,376
Weighted Average Assumptions [Abstract]
Expected volatility (in hundredths)	36.30%	39.50%	46.90%
Expected term (in years)	4.5	4.3	3.8
Risk-free interest rate (in hundredths)	1.40%	1.10%	1.80%
Dividend yield (in hundredths)	0.50%	0.60%	0.50%
Vesting period (in years)	3Y
Stock Option Activity [Abstract]
Outstanding at beginning of year (in shares)	2,955,000	3,286,000	3,594,000
Granted (in shares)	15,000	291,000	339,000
Exercised (in shares)	(405,000)	(616,000)	(628,000)
Forfeited (in shares)	(51,000)	(6,000)	(19,000)
Outstanding at end of year (in shares)	2,514,000	2,955,000	3,286,000
Exercisable at end of year (in shares)	2,157,000	2,053,000	2,255,000
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of year (in dollars per share)	$ 14.21	$ 11.28	$ 9.21
Granted (in dollars per share)	$ 40.59	$ 32.13	$ 21.38
Exercised (in dollars per share)	$ 10.98	$ 7.04	$ 4.79
Forfeited (in shares)	$ 24.54	$ 17.83	$ 14.10
Outstanding at end of year (in dollars per share)	$ 14.68	$ 14.21	$ 11.28
Exercisable, end of period (in dollars per share)	$ 12.35	$ 10.53	$ 8.52
Aggregate intrinsic value for outstanding stock options	65,043	57,930	36,342
Weighted average remaining contractual term for outstanding stock options (in years)	5.5
Aggregate intrinsic value for exercisable stock options outstanding	60,810
Weighted average remaining contractual term for exercisable stock options outstanding (in years)	5.0
Weighted-average fair value of options granted (in dollars per share)	$ 12.37	$ 10.10	$ 7.74
Total intrinsic value of stock options exercised	11,577	12,821	7,425
Restricted Stock [Member]
Non-vested restricted stock [Roll Foward]
Non-vested balance as of beginning of year (in shares)	363,000	418,000	347,000
Granted (in shares)	15,000	51,000	71,000
Vested (in shares)	(7,000)	(106,000)	0
Forfeited (in shares)	(17,000)	0	0
Non-vested balance as of end of year (in shares)	354,000	363,000	418,000
Weighted average grant date fair value [Abstract]
Non-vested balance as of beginning of year (in dollars per share)	$ 17.66	$ 14.56	$ 13.39
Granted (in dollars per share)	$ 41.34	$ 32.26	$ 21.34
Vested (in dollars per share)	$ 12.41	$ 12.47	$ 0
Forfeited (in dollars per share)	$ 19.12	$ 0	$ 0
Non-vested balance as of end of year (in dollars per share)	$ 18.77	$ 17.66	$ 14.56
Unrecognized compensation cost related to non-vested shares	$ 5,398	$ 8,795	$ 8,291
Weighted-average period of recognition for unrecognized compensation cost (in years)		2
Restricted Stock [Member] | Employee [Member]
Weighted Average Assumptions [Abstract]
Vesting period (in years)	4Y
Restricted Stock [Member] | Non-employee Director [Member]
Weighted Average Assumptions [Abstract]
Vesting period, minimum (in years)	4Y
Vesting period, maximum (in years)	7Y
1999 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Initial number of common stock shares reserved for issuance (in shares)	600,000
1999 Stock Plan [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of option grants exercisable after one year (in hundredths)	20.00%
Percentage of option grants exercisable after two years (in hundredths)	60.00%
Percentage of option grants exercisable after three years (in hundredths)	100.00%
Expiration period of options granted (in years)	10Y
1999 Stock Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchased under restricted stock purchase agreements, minimum (in shares)	1,000
Shares purchased under restricted stock purchase agreements, maximum (in shares)	20,250
Shares purchased under restricted stock purchase agreements, purchase price, minimum (in dollars per share)	$ 0.02
Shares purchased under restricted stock purchase agreements, purchase price, maximum (in dollars per share)	$ 0.07
Amended 1999 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Initial number of common stock shares reserved for issuance (in shares)	1,200,000
Increase in the number of shares of common stock reserved for issuance (in shares)	600,000
Second Amended 1999 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Initial number of common stock shares reserved for issuance (in shares)	6,000,000
ISO Plan [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period of options granted (in years)	10Y
Non-Qualified Plan [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period of options granted (in years)	10Y