Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
OPERATING ACTIVITIES
Net income	$ 14,152	$ 7,403
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	7,223	6,652
Interest accretion of convertible notes discount	2,238	0
Employee stock and stock option related compensation expense	2,505	1,401
Financing costs amortization	321	325
Foreign currency gains	(352)	(759)
Other non-cash operating activities	243	(291)
Increase (decrease) in cash resulting from changes in operating assets and liabilities:
Accounts receivable	5,391	(2,648)
Inventory	(17,074)	(12,911)
Unbilled contract revenues and other current assets	(1,662)	(255)
Accounts payable and other current liabilities	(27,619)	(12,548)
Customer advances and billings in excess of contract revenue	5,462	(7,207)
Net Cash Provided Used In Operating Activities	(9,172)	(20,838)
INVESTING ACTIVITIES
Capital expenditures	(6,345)	(4,266)
Other investing activities	0	388
Net Cash Used In Investing Activities	(6,345)	(3,878)
FINANCING ACTIVITIES
Principal payments on long-term debt	(1,625)	(1,625)
Proceeds from exercise of options	1,725	2,238
Tax benefit from exercise of stock options	6,355	2,452
Common stock repurchases	(4,473)	(1,090)
Net Cash Provided By Financing Activities	1,982	1,975
Effect of exchange rate changes on cash	(806)	4,625
Net decrease in cash and cash equivalents	(14,341)	(18,116)
Cash and cash equivalents at beginning of period	256,861	165,112
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 242,520	$ 146,996