Shareholders' Equity, Warrants (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Class of Warrant or Right [Line Items]
Number of shares warrants are entitled to purchase (in shares)	5.66	5.29	5.18
Cash receivable per share under warrant (in dollars per share)	$ 12.50
Term of warrants from the date of issue	7 years
Expiry date of warrants	Feb. 14, 2018
Series A Warrants [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 54.50
Warrants outstanding (in shares)	239,316	240,816
Series B Warrants [Member]
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)	$ 60.15
Warrants outstanding (in shares)	323,999	324,383