Segment Information and Concentration of Business Risk (Tables)

3 Months Ended

Mar. 31, 2018

Segment Information and Concentration of Business Risk [Abstract]

Segment Information

The following table shows our segment revenue and loss from operations for the three months ended March 31, 2018 and March 31, 2017 (as revised) (in thousands), respectively.

Three Months Ended March 31, 2018	Ionis Core		Akcea Therapeutics			Elimination of Intercompany Activity			Total
Revenue:
Commercial revenue:
SPINRAZA royalties	$	41,081	$	—		$	—		$	41,081
Licensing and other royalty revenue		942		—			—			942
Total commercial revenue	$	42,023	$	—		$	—		$	42,023
R&D revenue under collaborative agreements	$	90,517	$	17,108		$	(5,229	)	$	102,396
Total segment revenue	$	132,540	$	17,108		$	(5,229	)	$	144,419
Total operating expenses	$	105,544	$	47,435		$	(5,259	)	$	147,720
Income (loss) from operations	$	26,996	$	(30,327	)	$	30		$	(3,301	)

Three Months Ended March 31, 2017 (as revised)	Ionis Core		Akcea Therapeutics			Elimination of Intercompany Activity			Total
Revenue:
Commercial revenue:
SPINRAZA royalties	$	5,211	$	—		$	—		$	5,211
Licensing and other royalty revenue		2,590		—			—			2,590
Total commercial revenue	$	7,801	$	—		$	—		$	7,801
R&D revenue under collaborative agreements	$	153,382	$	6,094		$	(51,477	)	$	107,999
Total segment revenue	$	161,183	$	6,094		$	(51,477	)	$	115,800
Total operating expense	$	78,352	$	69,470		$	(51,507	)	$	96,315
Income (loss) from operations	$	82,831	$	(63,376	)	$	30		$	19,485

The following table shows our total assets by segment at March 31, 2018 and December 31, 2017 (as revised) (in thousands), respectively.

Total Assets	Ionis Core		Akcea Therapeutics		Elimination of Intercompany Activity			Total
March 31, 2018	$	1,349,044	$	252,466	$	(301,950	)	$	1,299,560
December 31, 2017 (as revised)	$	1,342,578	$	268,804	$	(288,608	)	$	1,322,774

Revenue from Significant Partners

We have historically funded our operations from collaborations with corporate partners and a relatively small number of partners have accounted for a significant percentage of our revenue. Revenue from significant partners, which is defined as ten percent or more of our total revenue, was as follows:

	Three Months Ended March 31,
	2018		2017
				(as revised)
Partner A		47 %		4 %
Partner B		36 %		25 %
Partner C		12 %		5 %
Partner D		0%		56%