Supplemental Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities	$ (10,098)	$ (4,273)
Investing Activities
Capital expenditures	(5,926)	(22,880)
Additions to prepaid royalties	(71)	(213)
Proceeds from disposals and divestitures	0	46
Purchases of marketable securities	(55,132)	(101,793)
Proceeds from sale or maturity of marketable securities and other investments	56,134	99,914
Investments in and advances to affiliates	(2,156)	(1,843)
Change in restricted cash	(12,108)	(3,532)
Cash used in investing activities	(19,259)	(30,301)
Financing Activities
Payments on term loan	0	(4,875)
Net payments on other debt	(5,410)	(4,810)
Expenses related to proposed debt restructuring	(2,213)	0
Debt financing costs	(18,403)	0
Transactions with affiliates, net	0	0
Cash used in financing activities	(26,026)	(9,685)
Decrease in cash and cash equivalents	(55,383)	(44,259)
Cash and cash equivalents, beginning of period	450,781	734,231
Cash and cash equivalents, end of period	395,398	689,972
Parent/Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities	(56,374)	(114,542)
Investing Activities
Capital expenditures	(22)	(450)
Additions to prepaid royalties	0	0
Proceeds from disposals and divestitures		0
Purchases of marketable securities	(55,132)	(101,793)
Proceeds from sale or maturity of marketable securities and other investments	56,134	99,914
Investments in and advances to affiliates		0
Change in restricted cash	0	0
Cash used in investing activities	980	(2,329)
Financing Activities
Payments on term loan		(4,875)
Net payments on other debt	(2,658)	(2,751)
Expenses related to proposed debt restructuring	(2,213)
Debt financing costs	(15,222)
Transactions with affiliates, net	21,150	130,144
Cash used in financing activities	1,057	122,518
Decrease in cash and cash equivalents	(54,337)	5,647
Cash and cash equivalents, beginning of period	337,646	572,185
Cash and cash equivalents, end of period	283,309	577,832
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities	43,335	96,944
Investing Activities
Capital expenditures	(5,904)	(22,430)
Additions to prepaid royalties	(71)	(213)
Proceeds from disposals and divestitures		46
Purchases of marketable securities	0	0
Proceeds from sale or maturity of marketable securities and other investments	0	0
Investments in and advances to affiliates	(2,156)	(1,843)
Change in restricted cash	0	0
Cash used in investing activities	(8,131)	(24,440)
Financing Activities
Payments on term loan		0
Net payments on other debt	(2,752)	(2,059)
Expenses related to proposed debt restructuring	0
Debt financing costs	0
Transactions with affiliates, net	(32,448)	(120,373)
Cash used in financing activities	(35,200)	(122,432)
Decrease in cash and cash equivalents	4	(49,928)
Cash and cash equivalents, beginning of period	100,428	150,358
Cash and cash equivalents, end of period	100,432	100,430
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities	2,941	13,325
Investing Activities
Capital expenditures	0	0
Additions to prepaid royalties	0	0
Proceeds from disposals and divestitures		0
Purchases of marketable securities	0	0
Proceeds from sale or maturity of marketable securities and other investments	0	0
Investments in and advances to affiliates	0	0
Change in restricted cash	(12,108)	(3,532)
Cash used in investing activities	(12,108)	(3,532)
Financing Activities
Payments on term loan		0
Net payments on other debt	0	0
Expenses related to proposed debt restructuring	0
Debt financing costs	(3,181)
Transactions with affiliates, net	11,298	(9,771)
Cash used in financing activities	8,117	(9,771)
Decrease in cash and cash equivalents	(1,050)	22
Cash and cash equivalents, beginning of period	12,707	11,688
Cash and cash equivalents, end of period	11,657	11,710
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
Purchases of marketable securities	0	0
Proceeds from sale or maturity of marketable securities and other investments	0	0
Investments in and advances to affiliates	0	0
Change in restricted cash	0	0
Cash used in investing activities	0	0
Financing Activities
Payments on term loan		0
Net payments on other debt	0	0
Expenses related to proposed debt restructuring	0
Debt financing costs	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