CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net loss	$ (32,068)	$ (5,060)
Adjustments for non-cash operating items:
Amortization of deferred revenue	(16,931)	(79,737)
Stock-based compensation	16,427	9,917
Amortization of debt discount and debt issuance costs	6,474	3,349
Depreciation on property and equipment	1,554	250
Accretion of discount on securities	(112)	(48)
Loss on disposal of equipment	35
Changes in operating assets and liabilities:
Receivable from collaboration partners	(28,861)	(1,956)
Prepaid expenses and other current assets	(3,733)	(1,982)
Other non-current assets	(1,383)	111
Accounts payable	1,871	314
Accrued expenses and other current liabilities	8,534	15,295
Interest payable		1,924
Other non-current liabilities	(137)	1,862
Net cash used in operating activities	(48,330)	(55,761)
Cash flows from investing activities:
Purchases of short-term investments	(144,926)	(199,914)
Maturities of short-term investments	225,000	75,000
Purchases of property and equipment	(4,651)	(5,825)
Change in restricted cash	(1,056)	(816)
Net cash provided by (used in) investing activities	74,367	(131,555)
Cash flows from financing activities:
Proceeds from issuance of Convertible Notes, net		250,987
Financing transaction costs		(614)
Proceeds from issuance of common stock under Medivation Equity Incentive Plan	3,649	11,326
Net cash provided by financing activities	3,649	261,699
Net increase in cash and cash equivalents	29,686	74,383
Cash and cash equivalents at beginning of period	71,301	70,136
Cash and cash equivalents at end of period	100,987	144,519
Non-cash investing activities:
Property and equipment expenditures incurred but not yet paid		$ 6,220