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Equity Incentive Plan (Stock Options Outstanding) (Details) - $ / shares | 3 Months Ended | 6 Months Ended
--- | --- | ---
Dec. 31, 2014 | Jun. 30, 2015
Number of Stock Options |  |
Beginning Balance (shares) |  | 5,138,072
Granted (shares) |  | 1,090,000
Forfeited (shares) |  | (60,000)
Exercised (shares) |  | (84,624)
Ending Balance (shares) | 5,138,072 | 6,083,448
Exercisable (shares) |  | 3,026,770
Weighted Average Grant Date Fair Value |  |
Beginning Balance (usd per share) |  | $ 3.08
Granted (usd per share) |  | 4.07
Forfeited (usd per share) |  | 3.91
Exercised (usd per share) |  | 2.30
Ending Balance (usd per share) | $ 3.08 | 3.29
Exercisable (usd per share) |  | 2.57
Weighted Average Exercise Price |  |
Beginning Balance (usd per share) |  | 10.04
Granted (usd per share) |  | 14.76
Forfeited (usd per share) |  | 13.13
Exercised (usd per share) |  | 7.09
Ending Balance (usd per share) | $ 10.04 | 10.89
Exercisable (usd per share) |  | $ 8.06
Weighted Average Contractual Life (years) |  |
Weighted Average Contractual Life, Outstanding | 7 years 5 months 9 days | 6 years 10 months 21 days
Weighted Average Contractual Life, Granted |  | 9 years 11 months 1 day
Weighted Average Contractual Life, Exercisable |  | 4 years 5 months 16 days

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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. + 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 (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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