Stock-Based Compensation Plans (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense for share-based payments	$ 3,245,975	$ 8,697,563
Compensation cost capitalized as part of inventory		197,254
Minimum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting period, years		one
Option expiration period, years	3	3
Maximum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting period, years		five
Option expiration period, years	7	7
Employee Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	20,163,395	20,163,395
Non-Employee Director Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	105,541	105,541
Option expiration period, years	10	10
Option vesting period, months		6
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares approved	1,200,000	1,200,000
ESPP discount rate		85.00%
ESPP discount rate recognized as compensation expense		15.00%
Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares approved	2,000,000	2,000,000
Restricted period, maximum, in years		10
Unearned stock-based compensation	6,876,831	6,876,831
Amortization expense	$ 519,169	$ 1,487,156

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Share-based compensation, restricted period.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Value of stock issued under share-based plans to employees or officers which is the unearned portion, accounted for under the fair value method.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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The discount rate from market value on purchase date that participants pay for shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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The weighted-average period between the balance sheet date and expiration date for fully vested and expected to vest options outstanding, which may be expressed in a decimal value for number of years.

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The amount by which an asset or assets increased resulting from the transaction in which equity securities were issued to pay for goods or nonemployee services.

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