Long-Term Debt (Schedule Of Long-Term Debt) (Details) - USD ($)	9 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Other	$ 8,487,000	$ 7,427,000
Less current portion	(30,163,000)	(32,775,000)
Long-term debt	2,740,554,000	2,741,178,000
Data Sublicense Agreement [Member]
Debt Instrument [Line Items]
Long-term debt	10,810,000	10,810,000
Senior Secured Term Loan Facility, Effective Interest Of 4.29% [Member] \| Senior Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt	1,615,308,000	1,621,981,000
Long-term debt, face amount	$ 1,696,000,000
Maturity date	Nov. 02, 2018
Long-term debt, unamortized discount	$ 17,494,000	23,511,000
Long-term debt, effective interest rate	4.29%
Senior Secured Term Loan Facility, Effective Interest Of 4.54% [Member] \| Senior Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt	$ 154,317,000	154,666,000
Long-term debt, face amount	$ 160,000,000
Maturity date	Nov. 02, 2018
Long-term debt, unamortized discount	$ 2,483,000	3,334,000
Long-term debt, effective interest rate	4.54%
Senior Secured Revolving Credit Facility [Member] \| Senior Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	$ 125,000,000
Senior Secured Revolving Credit Facility, Due November 2, 2016 [Member] \| Senior Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	$ 28,400,000
Maturity date	Nov. 02, 2016
Senior Secured Revolving Credit Facility, Due August 3, 2018 [Member] \| Senior Credit Facilities [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	$ 96,600,000
Maturity date	Aug. 03, 2018
11% Senior Notes Due December 31, 2019 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 369,673,000	368,701,000
Long-term debt, face amount	$ 375,000,000
Long-term debt, stated interest rate	11.00%
Maturity date	Dec. 31, 2019
Long-term debt, unamortized discount	$ 5,327,000	6,299,000
Long-term debt, effective interest rate	11.53%
11.25% Senior Notes Due December 31, 2020 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 367,504,000	366,529,000
Long-term debt, face amount	$ 375,000,000
Long-term debt, stated interest rate	11.25%
Maturity date	Dec. 31, 2020
Long-term debt, unamortized discount	$ 7,496,000	8,471,000
Long-term debt, effective interest rate	11.85%
6% Senior Notes Due February 15, 2021 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 244,618,000	243,839,000
Long-term debt, face amount	$ 250,000,000
Long-term debt, stated interest rate	6.00%
Maturity date	Feb. 15, 2021
Long-term debt, unamortized discount	$ 5,382,000	$ 6,161,000
Long-term debt, effective interest rate	6.57%

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount, after accumulated amortization, of debt discount.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount of long-term debt classified as other.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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