Capital Stock (Narrative) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Capital Stock [Abstract]    
Common stock, shares authorized 600,000,000 600,000,000
Common stock, par value $ 0.001 $ 0.001
Preferred stock, shares authorized 10,000,000 10,000,000
Preferred stock, par value $ 0.001 $ 0.001
Common stock shares outstanding 172,363,259 172,104,720
Reserved for future issuance 23,824,039 22,089,643
Restricted Stock Units, Issued 2,386,673 3,341,132
Unvested Restricted Stock Units 3,580,009 5,011,698