Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities
Net income (loss)	$ 38,059	$ 29,111	$ (9,630)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Depreciation and amortization	9,724	6,066	5,342
Net loss on disposal of equipment	84	234
Stock-based compensation	2,297	2,252	937
Stock issued to board of directors	162
Realized gain on investments		(8)	(47)
Deferred taxes	13,447
Excess tax benefits from stock-based compensation	(1,404)
Changes in operating assets and liabilities:
Accounts receivable	(13,968)	(13,709)	(2,425)
Inventories	(11,948)	(4,464)	1,285
Other inventory supplies	(9,929)	(5,646)	1,436
Prepaid expenses and other assets	(3,993)	(548)	38
Accounts payable	3,683	7,129	(445)
Accrued payroll	(951)	2,020	(162)
Corporate income and franchise taxes	212	236	(84)
Advance payments	(1,094)	1,076
Accrued and other current liabilities	231	310	463
Net cash provided by (used in) operating activities	24,612	24,059	(3,292)
Cash flows from investing activities
Purchases of property and equipment	(48,228)	(49,429)	(5,530)
Proceeds from disposal of assets		143
Purchase of investments	(9,439)	(55,416)	(693)
Proceeds from sale of investments	25,000	30,000	7,922
Net cash (used in) provided by investing activities	(32,667)	(74,702)	1,699
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs of $4,130		61,720
Proceeds from exercise of options	742	1,640	420
Restricted cash	344	(525)	(3)
Purchase of treasury stock	(6,487)		(2,577)
Excess tax benefits from stock-based compensation	1,404
Net cash (used in) provided by financing activities	(3,997)	62,835	(2,160)
Net effect of currency translation	269	21	(16)
Net (decrease) increase in cash and cash equivalents	(11,783)	12,213	(3,769)
Cash and cash equivalents, beginning of year	16,073	3,860	7,629
Cash and cash equivalents, end of year	4,290	16,073	3,860
Supplemental disclosure of cash flow information
Cash paid for income taxes	6,050
Supplemental disclosure of non cash items of cash flow information
Unrealized loss on investments	(42)	(9)	(126)
Deferred offering costs included in accounts payable			61
Stock-based compensation incurred for accrued director's fees			$ 36