Summary Of Significant Accounting Policies (Activity In Gold Bullion) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2012 oz	Mar. 31, 2011 oz	Dec. 31, 2011 oz
Summary Of Significant Accounting Policies [Abstract]
Beginning balance, Ounces	5,498,800	3,783,000	3,783,000
Gold contributed, Ounces	367,500		2,333,900
Gold distributed, Ounces	(49,700)		(606,800)
Gold sold, Ounces	(3,500)		(11,300)
Ending balance, Ounces	5,813,100		5,498,800
Beginning balance, Average Cost	$ 6,572,102	$ 3,568,036	$ 3,568,036
Gold contributed, Average Cost	630,526		3,660,287
Gold distributed, Average Cost	(61,018)		(644,033)
Gold sold, Average Cost	(4,215)		(12,188)
Ending balance, Average Cost	7,137,395		6,572,102
Beginning balance, Fair Value	8,418,739	5,317,017	5,317,017
Gold contributed, Fair Value	630,526		3,660,287
Gold distributed, Fair Value	(82,366)		(915,939)
Gold sold, Fair Value	(5,851)		(17,758)
Adjustment for realized gain, Fair Value	22,984		277,476
Adjustment for unrealized gain on gold bullion, Fair Value	680,368		97,656
Ending balance, Fair Value	9,664,400		8,418,739
Gold distributed, Realized Gain (Loss)	21,348		271,906
Gold sold, Realized Gain (Loss)	1,636	956	5,570
Ending balance, Realized Gain (Loss)	$ 22,984		$ 277,476