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Stock-Based Compensation Plans (Narrative) (Details) (USD $) | 3 Months Ended |  |  | 3 Months Ended | 12 Months Ended | 3 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2014 | Mar. 31, 2014 Employee Stock Option Plan [Member] | Feb. 28, 2014 Employee Stock Option Plan [Member] | Mar. 31, 2014 Employee Stock Option Plan [Member] Minimum | Mar. 31, 2014 Employee Stock Option Plan [Member] Maximum | Mar. 31, 2014 Non-Employee Director Stock Option Plan [Member] | Dec. 31, 2013 Employee Stock Purchase Plan [Member] | Mar. 31, 2014 Restricted Stock Plan [Member] | Mar. 31, 2014 Equity Incentive Plans [Member] plan | Mar. 31, 2014 Stock Options [Member] plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Number of plans (in plans) |  |  |  |  |  |  |  |  | 4 | 2
Compensation expense for share-based payments | $ 4,009,346 |  |  |  |  |  |  |  |  |
Compensation cost capitalized as part of inventory | 239,959 |  |  |  |  |  |  |  |  |
Number if shares available for grant (in shares) |  |  | 12,000,000 |  |  |  |  |  |  |
Option vesting period |  |  |  | 1 year | 5 years | 6 months |  |  |  |
Option expiration period |  |  |  | 2 years | 7 years | 10 years |  |  |  |
Unrecognized compensation cost |  | 25,136,376 |  |  |  | 0 |  |  |  |
Options granted (in shares) |  |  |  |  |  | 84,000 |  |  |  |
Shares approved (in shares) |  |  |  |  |  |  | 1,000,000 |  |  |
ESPP discount rate |  |  |  |  |  |  | 85.00% |  |  |
ESPP discount rate recognized as compensation expense |  |  |  |  |  |  | 15.00% |  |  |
Options granted (in shares) |  |  |  |  |  |  |  | 2,000,000 |  |
Restricted period, maximum, in years |  |  |  |  |  |  |  | 10 years |  |
Unearned stock-based compensation |  |  |  |  |  |  |  | 9,808,075 |  |
Amortization expense |  |  |  |  |  |  |  | $ 732,734 |  |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
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- Definition Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6418621&loc=d3e17540-113929 + Details
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- Definition Period 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, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Discount rate from fair value on purchase date that participants pay for shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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