Statements of Changes in Shareholders' Equity (Deficit) (USD $) In Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
Statements of Changes in Shareholders' Equity (Deficit)
Shareholders' equity (deficit) - beginning of period	$ (1,748,981)	$ (878,372)
Net income	124,490	32,297
Adjustment of redeemable capital shares to redemption value	(380,468)	(902,906)
Shareholders' equity (deficit) - end of period	$ (2,004,959)	$ (1,748,981)