Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Schedule of Cash as Reported in Consolidated Statements of Cash Flows

Cash as reported in the consolidated statements of cash flows includes the aggregate amounts of cash and cash equivalents and restricted cash, and consists of the following (in thousands):

	December 31, 2018		December 31, 2017		December 31, 2016
Cash and cash equivalents	$	138,951	$	181,568	$	188,480
Restricted cash (SRX Cardio)		30		173		178
Restricted cash for royalty payments to HealthCare Royalty Partners and its affiliates ("HCR")		1,032		—		—
Total cash balance in consolidated statements of cash flows	$	140,013	$	181,741	$	188,658

Percentage of Revenue from Significant Customers

Customers who accounted for 10% or more of total net revenues were as follows:

	2018	2017	2016
Bayer Pharma, AG and Janssen Pharmaceuticals, Inc.	19%	29%	27%
Daiichi Sankyo, Inc.	16%	33%	29%
Bristol-Myers Squibb Company and Pfizer Inc.	*	22%	19%
Dermavant Sciences GmbH	*	16%	25%

* Less than 10%

Comparison of Reported Consolidated Balance Sheet, Statement of Operations Under New Guidance

the following adjustments were made to the consolidated balance sheet as of January 1, 2018 (in thousands):

	As of January 1, 2018
	As Revised Under ASC 606			Without the Adoption of ASC 606			Effect of Change
Assets:
Unbilled - collaboration and license revenue	$	6,694		$	—		$	6,694
Trade and other receivables, net		2,706			—			2,706
Prepaid expenses and other current assets		—			2,706			(2,706	)
Liabilities:
Deferred revenue, current portion		6,354			11,169			(4,815	)
Deferred revenue, long-term		1,269			18,798			(17,529	)
Stockholders' equity:
Accumulated deficit	$	(1,175,481	)	$	(1,204,519	)	$	29,038

The following table compares the reported consolidated balance sheet and statement of operations information to the balances that do not reflect the adoption of ASC 606 as of and for the year ended December 31, 2018 (in thousands, except for per share data):

	As of December 31, 2018
	As Reported			Balances Without the Adoption of ASC 606			Effect of Change
Assets:
Unbilled - collaboration and license revenue	$	9,880		$	—		$	9,880
Trade and other receivables, net		1,243			—			1,243
Prepaid expenses and other current assets		—			1,243			(1,243	)
Liabilities:
Deferred revenue, current portion		1,847			4,589			(2,742	)
Deferred revenue, long-term		4,488			22,695			(18,207	)
Stockholders' equity:
Accumulated deficit	$	(1,525,704	)	$	(1,556,533	)	$	30,829

	Year Ended December 31, 2018
	As Reported			Balances Without the Adoption of ASC 606			Effect of Change
Revenue:
Collaboration and license revenue	$	16,013		$	11,682		$	4,331
Operating expenses:
Research and development		216,205			213,657			2,548
Loss from operations		(345,320	)		(347,103	)		1,783
Net loss		(350,544	)		(352,327	)		1,783
Net loss attributable to Portola		(350,223	)		(352,006	)		1,783
Net loss per share attributable to Portola common stockholders: Basic and diluted	$	(5.31	)	$	(5.33	)	$	0.03