Consolidated Statements Of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Cash flows from operating activities
Net income	$ 29,012	$ 5,463
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	4,265	2,790
Loss on disposal of assets	7	305
Stock-based compensation	1,750	1,013
Realized gain on investments		(8)
Deferred tax assets	(3,329)
Excess tax benefits from stock-based compensation	(10,711)
Changes in operating assets and liabilities:
Accounts receivable	(12,567)	(4,272)
Inventories	(1,442)	(237)
Other inventory supplies	(3,589)	(1,270)
Prepaid expenses and other current assets	141	(295)
Accounts payable	(825)	1,213
Accrued payroll	(888)	725
Corporate income and franchise taxes	12,389	(20)
Advanced payments	(719)	(17)
Accrued and other current liabilities	1,264	954
Net cash provided by operating activities	14,758	6,344
Cash flows from investing activities
Purchases of property and equipment	(25,385)	(19,692)
Purchases of investments		(47,687)
Proceeds from sale of investments	3,113	15,500
Net cash (used in) investing activities	(22,272)	(51,879)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs of $4,063		61,789
Proceeds from exercise of options	741	1,251
Restricted cash	(9)	(498)
Excess tax benefits from stock-based compensation	10,711
Net cash provided by financing activities	11,443	62,542
Net effect of currency translation	(29)	43
Net increase in cash and cash equivalents	3,900	17,050
Cash and cash equivalents, beginning of period	16,073	3,860
Cash and cash equivalents, end of period	19,973	20,910
Supplemental disclosures of cash flow information Cash paid for income taxes	5,420
Supplemental disclosures of non-cash transactions Unrealized loss on investments	$ 18	$ 86