Senior Long-Term Debt And Other Debt (Summary Of Senior Long-Term Debt And Other Debt) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Senior long-term debt and other debt	$ 2,241,427	$ 2,253,594
Unsecured Senior Notes [Member] \| 7.20% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 92,436	$ 94,155
Debt instrument, interest rate	7.20%	7.20%
Debt Instrument, unamortized premium	$ 1,808	$ 3,526
Unsecured Senior Notes [Member] \| 7.125% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 346,940	$ 348,657
Debt instrument, interest rate	7.125%	7.125%
Debt instrument, unamortized discount	$ 1,060	$ 1,343
Unsecured Senior Notes [Member] \| 6.25% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 394,517	$ 403,172
Debt instrument, interest rate	6.25%	6.25%
Debt Instrument, unamortized premium	$ 44,519	$ 53,172
Unsecured Senior Notes [Member] \| 5.35% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 248,881	$ 248,675
Debt instrument, interest rate	5.35%	5.35%
Debt instrument, unamortized discount	$ 1,119	$ 1,325
Unsecured Senior Notes [Member] \| 4.90% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 348,185	$ 347,905
Debt instrument, interest rate	4.90%	4.90%
Debt instrument, unamortized discount	$ 1,815	$ 2,095
Unsecured Senior Notes [Member] \| 3.625% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 248,542	$ 248,341
Debt instrument, interest rate	3.625%	3.625%
Debt instrument, unamortized discount	$ 1,458	$ 1,659
Unsecured Senior Notes [Member] \| 7.35% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 198,028	$ 197,922
Debt instrument, interest rate	7.35%	7.35%
Debt instrument, unamortized discount	$ 1,972	$ 2,078
Unsecured Senior Notes [Member] \| 5.0% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 243,897	$ 243,673
Debt instrument, interest rate	5.00%	5.00%
Debt instrument, unamortized discount	$ 6,103	$ 6,327
Subsidiary And Other Debt [Member]
Debt Instrument [Line Items]
Senior long-term debt and other debt	$ 120,001	$ 121,094
Debt instrument, interest rate, percentage rate range, minimum	1.90%
Debt instrument, interest rate, percentage rate range, maximum	6.50%

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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Maximum contractual interest rate for funds borrowed, under the debt agreement.

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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.22(a)(2))
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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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=6451184&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ 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 210.7-03.16(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
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