Subsequent Events (Details) (Subsequent events, Common stock, GSK, USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended
	Feb. 14, 2014
Subsequent events | Common stock | GSK
Subsequent events
Agreement to issue stock, number of shares	342,229
Agreement to issue stock in private placement, price per shares (in dollars per share)	$ 37.55
Agreement to issue stock in private placement, aggregate purchase price	$ 12.9