Issue price of the notes as a percent of face value.

No definition available.

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- Definition

Maximum percentage of the unsecured notes that can be redeem early prior to the specified date.

+ References

No definition available.

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- Definition

Principal amount of senior unsecured note that was tendered

+ References

No definition available.

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- Definition

The redemption premium for notes repaid up to a specified percentage of the total notes outstanding prior to the specified date.

+ References

No definition available.

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- Definition

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

+ References

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

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- Definition

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

+ 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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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

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

+ References

+ Details

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- Definition

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

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
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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.

+ Details

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- Definition

The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

+ Details

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Debt Debt (Senior Unsecured Notes) (Details) - USD ($)	1 Months Ended	12 Months Ended
Debt Debt (Senior Unsecured Notes) (Details) - USD ($)	Jul. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jul. 23, 2015	May 21, 2015	May 15, 2014	Feb. 08, 2013	Feb. 01, 2012	Nov. 30, 2010
Debt Instrument [Line Items]
Senior unsecured notes, principal	$ 750,000,000
Senior unsecured notes		$ 1,813,169,000	$ 1,807,054,000
Note tender offer			300,100,000
Redemption premium			49,900,000
Loss on extinguishment of debt		0	(19,225,000)	$ 0
Proceeds from issuance of debt, net of discount	$ 728,600,000
7.875% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal									$ 100,000,000	$ 250,000,000
Debt instrument, stated rate									7.875%	7.875%
Debt instrument percentage, of fair value										101.00%
Unsecured Debt [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal									$ 350,000,000
Debt Instrument, effective interest rate									7.682%
6.00% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal		400,000,000	400,000,000			$ 400,000,000
Debt instrument, stated rate						6.00%
Senior unsecured notes		$ 393,242,000	392,175,000
Redemption premium for notes		106.00%
5.750% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal		$ 350,000,000	350,000,000					$ 350,000,000
Debt instrument, stated rate								5.75%
Senior unsecured notes		345,837,000	344,817,000
6.750% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal		750,000,000	750,000,000		$ 750,000,000
Debt instrument, stated rate					6.75%
Senior unsecured notes		$ 730,704,000	727,572,000
Redemption premium for notes		106.75%
5.625% Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal		$ 350,000,000	350,000,000				$ 350,000,000
Debt instrument, stated rate							5.625%
Senior unsecured notes		$ 343,386,000	$ 342,490,000
Redemption premium for notes		105.625%
Early debt redemption, maximum percentage of principal			35.00%