Statements of Changes in Shareholders’ Equity (Deficit) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Shareholders’ equity (deficit) – beginning of period	$ (2,332,728)	$ (1,846,637)	$ (1,748,981)
Net income (loss)	(628,066)	136,332	258,847
Adjustment of redeemable capital Shares to redemption value	2,960,794	(622,423)	(356,503)
Shareholders’ equity (deficit) – end of period	$ 0	$ (2,332,728)	$ (1,846,637)