| In millions, except per share items | Jun-30-15 | Mar-31-15 | Dec-31-14 | Sep-30-14 | Jun-30-14 | Mar-31-14 | Dec-31-13 | Sep-30-13 |
| | 10-Q | 10-Q | 10-K | 10-Q | 10-Q | 10-Q | 10-K | 10-Q |
| Operating activities | | | | | | | | |
| Net loss | -201.6 | -183.9 | -224.5 | -214.3 | -114.5 | -121.4 | -66.0 | -70.1 |
| |
| Adjustments to reconcile net loss to net cash used in operating activities: | | | | | | | | |
| Amortization of premium on marketable securities | 1.2 | 1.2 | | 1.2 | 0.6 | 0.6 | | |
| Amortization of debt discount and issuance cost | 1.7 | 1.4 | 1.3 | 1.1 | 0.6 | 0.5 | 0.4 | 0.4 |
| Depreciation and amortization | 0.4 | | | | 0.0 | | | |
| Non-cash in-process research and development | | | | 106.1 | | 53.0 | | |
| Stock-based compensation | 23.6 | 19.9 | 18.4 | 16.8 | 9.7 | 9.4 | 7.4 | 6.2 |
| Changes in assets and liabilities: | | | | | | | | |
| Inventory | -4.0 | | | | | | | |
| Prepaid expenses and other current assets | -1.1 | 0.7 | -1.2 | -2.0 | -1.6 | -2.0 | -0.4 | 0.8 |
| Restricted cash | | | | 14.7 | 11.1 | 14.8 | 13.1 | 9.8 |
| Other assets | -0.4 | -1.3 | -1.3 | -1.6 | -0.9 | | | |
| Accounts payable and other accrued liabilities | 16.1 | 6.4 | 2.9 | 0.0 | 0.4 | -1.2 | -0.6 | 1.3 |
| Deferred development funds | | | | -7.3 | | -14.2 | -15.2 | -13.3 |
| Other liabilities | 0.7 | 1.8 | 1.8 | 1.1 | 0.4 | 0.0 | 0.0 | |
| Net cash used in operating activities | -106.7 | -95.8 | -89.0 | -83.8 | -49.8 | -59.9 | -60.2 | -65.1 |
| |
| Investing activities | | | | | | | | |
| Purchases of marketable securities | -112.0 | | -63.5 | -87.4 | -54.2 | -41.1 | -63.8 | |
| Proceeds from sales of marketable securities | 68.9 | 65.0 | 47.3 | 37.2 | 34.1 | 14.0 | 7.4 | |
| Proceeds from maturities of marketable securities | 68.9 | 65.0 | 47.3 | 37.2 | 34.1 | 14.0 | 7.4 | |
| Investment in property and equipment | -2.6 | -3.1 | -2.8 | -2.7 | -0.8 | -0.1 | | |
| Other investing activity | 0.5 | | | | | | | |
| Net cash (used in) provided by investing activities | -42.3 | 12.0 | -15.1 | -48.9 | -20.9 | -59.5 | -88.9 | -61.9 |
| |
| Financing activities | | | | | | | | |
| Repayment of notes payable | -12.2 | -8.9 | -8.7 | -8.6 | -5.2 | -4.2 | -2.8 | |
| Proceeds from common stock option and warrant exercises | 6.0 | | | | 1.2 | | | |
| Net cash (used in) provided by financing activities | 129.8 | 128.6 | -6.1 | 119.4 | 121.7 | 133.2 | 143.7 | 99.4 |
| |
| Repayment on credit facility | | | | | | | | |
| Net (decrease) increase in cash and cash equivalents | -19.2 | 44.8 | -110.2 | -13.4 | 51.0 | 13.9 | -5.5 | -27.6 |
| Cash and cash equivalents at beginning of period | | 140.7 | | 223.0 | | 190.8 | | |
| Cash and cash equivalents at end of period | 121.5 | 185.5 | 112.8 | 209.7 | 162.5 | 204.7 | 153.1 | 131.0 |
| |
| Supplemental disclosures | | | | | | | | |
| Issuance of common stock to Bayer | | | | 62.9 | | 31.4 | | |
| Note payable issued to Bayer at fair value | | | | 43.2 | | 21.6 | | |
| Interest expense paid in cash | 2.3 | | 1.2 | 1.3 | 1.1 | | 1.6 | |