Income And Deferred Taxes (Narrative) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Schedule Of Income Tax [Line Items]
Permanent differences	$ 218,068,000		$ (2,721,000)
Impairment charges	1,057,819,000		20,309,000
Income tax paid	5,139,000	29,544,000	16,270,000
Net operating loss carry-forward	23,332,000
Additional non cash valuation allowance for deferred tax assets	$ 61,300,000