Collaborative Arrangements and Licensing Agreements, Traditional Pharmaceutical Alliances and Licensing - AstraZeneca (Details) $ in Thousands	1 Months Ended					3 Months Ended		6 Months Ended		7 Months Ended
	Jul. 31, 2015 USD ($)	Nov. 30, 2014 USD ($)	Aug. 31, 2013 USD ($)	Jun. 30, 2013 USD ($)	Dec. 31, 2012 USD ($) Target Drug	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2013 USD ($) Drug
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned						$ 120,428	$ 57,076	$ 183,012	$ 85,237
AstraZeneca [Member] | Collaborations and Licensing Agreements [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned						700	$ 15,600	1,500	$ 19,100
Deferred revenue						3,200		3,200
AstraZeneca [Member] | Collaborations and Licensing Agreements [Member] | ISIS-STAT3-2.5 [Member] | Phase 2 Study [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payments to be earned						17,500		17,500
AstraZeneca [Member] | Agreement Entered into in December 2012 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of targets | Target					5
Number of drugs the collaborative partner may license under a separate research program | Drug					3
Upfront fee received				$ 6,000	$ 25,000					$ 31,000
Revenue earned										$ 11,500
Cumulative payments received						63,500		63,500
Next prospective milestone						10,000		10,000
AstraZeneca [Member] | Agreement Entered into in December 2012 [Member] | Pre-specified Events [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable						858,000		858,000
AstraZeneca [Member] | Agreement Entered into in December 2012 [Member] | Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable						238,000		238,000
AstraZeneca [Member] | Agreement Entered into in December 2012 [Member] | Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable						620,000		620,000
AstraZeneca [Member] | Agreement Entered into in December 2012 [Member] | Three Drugs [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of drugs the collaborative partner may license under a separate research program | Drug										3
Deferred revenue				7,600						$ 7,600
AstraZeneca [Member] | Agreement Entered into in December 2012 [Member] | ISIS-STAT3-2.5 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue				$ 11,900						$ 11,900
AstraZeneca [Member] | Amended Agreement Entered into in October 2014 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Milestone payment received		$ 7,500
AstraZeneca [Member] | Agreement Entered into in August 2013 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received						800		800
Next prospective milestone						3,300		3,300
Upfront fee recorded as deferred revenue			$ 800
AstraZeneca [Member] | Agreement Entered into in August 2013 [Member] | License Fee and Substantive Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable						163,200		163,200
AstraZeneca [Member] | Agreement Entered into in August 2013 [Member] | Research and Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable						45,300		45,300
AstraZeneca [Member] | Agreement Entered into in August 2013 [Member] | Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable						$ 105,000		$ 105,000
AstraZeneca [Member] | Agreement Entered into in July 2015 [Member] | Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Near-term payments	$ 65,000
AstraZeneca [Member] | Agreement Entered into in July 2015 [Member] | Maximum [Member] | Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective milestone	25,000
AstraZeneca [Member] | Agreement Entered into in July 2015 [Member] | License Fee and Substantive Milestones [Member] | Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Minimum amount of payments receivable	4,000,000
AstraZeneca [Member] | Agreement Entered into in July 2015 [Member] | Development Milestones [Member] | Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable	1,100,000
AstraZeneca [Member] | Agreement Entered into in July 2015 [Member] | Regulatory Milestones [Member] | Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable	$ 2,900,000