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

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

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

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- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

+ References

No definition available.

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- Definition

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

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-Publisher FASB
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Senior Long-Term Debt (Narrative) (Details) - USD ($) $ in Thousands			1 Months Ended	3 Months Ended		6 Months Ended
	May 05, 2016	Apr. 05, 2016	Apr. 30, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Debt Instrument [Line Items]
Loss on early extinguishment of debt				$ (44,100)	$ 0	$ (44,100)	$ 0
5.0% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 100,000	$ 400,000
Debt instrument, interest rate	5.00%	5.00%
Net proceeds from issuance of unsecured senior notes	$ 100,800	$ 392,300
7.35% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			7.35%
Debt instrument, repurchased face amount			$ 70,200
Early repayment of senior debt			$ 95,000
7.125% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			7.125%
Debt instrument, repurchased face amount			$ 108,800
Early repayment of senior debt			$ 126,400
7.20% Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate				7.20%		7.20%
Debt instrument, principal amount outstanding				$ 90,600		$ 90,600