Supplemental Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			$ (79,682)	$ 1,990
Investing Activities
Capital expenditures	$ (9,889)	$ (22,955)	(109,250)	(118,701)
Additions to prepaid royalties			(5,808)	(3,604)
Proceeds from disposals and divestitures			1,020	50,971
Purchases of marketable securities			(203,094)	(181,546)
Proceeds from sales of short term investments			248,362	178,293
Investments in and advances to affiliates			(7,944)	(13,393)
Cash used in investing activities			(76,714)	(87,980)
Financing Activities
Payments on term loan			(14,625)	(14,625)
Debt financing costs			0	(2,219)
Net payments on other debt			(12,192)	(10,187)
Expenses related to debt restructuring			(11,498)	0
Dividends paid			0	(2,123)
Deposits of restricted cash			(44,732)	(6)
Other			0	(15)
Transactions with affiliates, net			0	0
Cash used in financing activities			(83,047)	(29,175)
Decrease in cash and cash equivalents			(239,443)	(115,165)
Cash and cash equivalents, beginning of period			734,231	911,099
Cash and cash equivalents, end of period	494,788	795,934	494,788	795,934
Parent/Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			(353,386)	(342,497)
Investing Activities
Capital expenditures			(956)	(1,195)
Additions to prepaid royalties			0	0
Proceeds from disposals and divestitures			0	46,634
Purchases of marketable securities			(203,094)	(181,546)
Proceeds from sales of short term investments			248,362	178,293
Investments in and advances to affiliates			(788)	(2,047)
Cash used in investing activities			43,524	40,139
Financing Activities
Payments on term loan			(14,625)	(14,625)
Debt financing costs				(2,219)
Net payments on other debt			(5,814)	(6,814)
Expenses related to debt restructuring			(11,498)
Dividends paid				(2,123)
Deposits of restricted cash			0	0
Other				(15)
Transactions with affiliates, net			132,257	162,643
Cash used in financing activities			100,320	136,847
Decrease in cash and cash equivalents			(209,542)	(165,511)
Cash and cash equivalents, beginning of period			572,185	799,333
Cash and cash equivalents, end of period	362,643	633,822	362,643	633,822
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			279,503	360,036
Investing Activities
Capital expenditures			(108,294)	(117,506)
Additions to prepaid royalties			(5,808)	(3,604)
Proceeds from disposals and divestitures			1,020	4,337
Purchases of marketable securities			0	0
Proceeds from sales of short term investments			0	0
Investments in and advances to affiliates			(7,156)	(11,346)
Cash used in investing activities			(120,238)	(128,119)
Financing Activities
Payments on term loan			0	0
Debt financing costs				0
Net payments on other debt			(6,378)	(3,373)
Expenses related to debt restructuring			0
Dividends paid				0
Deposits of restricted cash			0	0
Other				0
Transactions with affiliates, net			(182,761)	(178,603)
Cash used in financing activities			(189,139)	(181,976)
Decrease in cash and cash equivalents			(29,874)	49,941
Cash and cash equivalents, beginning of period			150,358	100,418
Cash and cash equivalents, end of period	120,484	150,359	120,484	150,359
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			(5,799)	(15,549)
Investing Activities
Capital expenditures			0	0
Additions to prepaid royalties			0	0
Proceeds from disposals and divestitures			0	0
Purchases of marketable securities			0	0
Proceeds from sales of short term investments			0	0
Investments in and advances to affiliates			0	0
Cash used in investing activities			0	0
Financing Activities
Payments on term loan			0	0
Debt financing costs				0
Net payments on other debt			0	0
Expenses related to debt restructuring			0
Dividends paid				0
Deposits of restricted cash			(44,732)	(6)
Other				0
Transactions with affiliates, net			50,504	15,960
Cash used in financing activities			5,772	15,954
Decrease in cash and cash equivalents			(27)	405
Cash and cash equivalents, beginning of period			11,688	11,348
Cash and cash equivalents, end of period	11,661	11,753	11,661	11,753
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			0	0
Investing Activities
Capital expenditures			0	0
Additions to prepaid royalties			0	0
Proceeds from disposals and divestitures			0	0
Purchases of marketable securities			0	0
Proceeds from sales of short term investments			0	0
Investments in and advances to affiliates			0	0
Cash used in investing activities			0	0
Financing Activities
Payments on term loan			0	0
Debt financing costs				0
Net payments on other debt			0	0
Expenses related to debt restructuring			0
Dividends paid				0
Deposits of restricted cash			0	0
Other				0
Transactions with affiliates, net			0	0
Cash used in financing activities			0	0
Decrease in cash and cash equivalents			0	0
Cash and cash equivalents, beginning of period			0	0
Cash and cash equivalents, end of period	$ 0	$ 0	$ 0	$ 0