CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 683,287	$ 278,820
Short-term investments	1,816,257	1,805,252
Contracts receivable	63,034	12,759
Inventories	18,180	8,582
Other current assets	139,839	102,473
Total current assets	2,720,597	2,207,886
Property, plant and equipment, net	153,651	132,160
Patents, net	25,674	24,032
Long-term deferred tax assets	305,557	290,796
Deposits and other assets	27,633	12,910
Total assets	3,233,112	2,667,784
Current liabilities:
Accounts payable	16,067	28,660
Accrued compensation	37,357	29,268
Accrued liabilities	66,769	47,503
Income taxes payable	32,514	858
Current portion of long-term obligations	2,026	13,749
Current portion of deferred contract revenue	118,272	160,256
Total current liabilities	273,005	280,294
Long-term deferred contract revenue	490,060	567,359
Long-term obligations, less current portion	15,543	4,914
Long-term mortgage debt	59,913	59,842
Total liabilities	1,548,565	1,480,624
Stockholders' equity:
Common stock, $0.001 par value; 300,000,000 shares authorized, 140,339,615 and 137,928,828 shares issued and outstanding at December 31, 2019 and December 31, 2018, respectively	140	138
Additional paid-in capital	2,203,778	2,047,250
Accumulated other comprehensive loss	(25,290)	(32,016)
Accumulated deficit	(707,534)	(967,293)
Total Ionis stockholders' equity	1,471,094	1,048,079
Noncontrolling interest in Akcea Therapeutics, Inc.	213,453	139,081
Total stockholders' equity	1,684,547	1,187,160
Total liabilities and stockholders' equity	3,233,112	2,667,784
0.125 Percent Convertible Senior Notes [Member]
Current liabilities:
Convertible senior notes	434,711	0
1 Percent Convertible Senior Notes [Member]
Current liabilities:
Convertible senior notes	$ 275,333	$ 568,215