Principal amount of senior unsecured note that was tendered

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- Definition

Proceeds used to repay unsecured debt principal

+ 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
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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
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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.

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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
-Paragraph 2
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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

The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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-Name Accounting Standards Codification
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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.

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Debt (Senior Unsecured Notes) (Details) - USD ($)					12 Months Ended
Debt (Senior Unsecured Notes) (Details) - USD ($)	Dec. 11, 2017	Sep. 01, 2017	Aug. 14, 2017	Jul. 23, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jul. 31, 2015	May 21, 2015	May 15, 2014	Feb. 08, 2013	Feb. 01, 2012
Debt Instrument [Line Items]
Loss on extinguishment of debt					$ 6,242,000	$ 0	$ 19,225,000
Proceeds from issuance of unsecured debt					1,000,000,000	0	1,139,718,000
Enterprise Offshore Acquisition [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal								$ 750,000,000
5.750% senior unsecured notes
Debt Instrument [Line Items]
Senior unsecured notes, principal					145,170,000	350,000,000					$ 350,000,000
Debt instrument, stated rate											5.75%
Proceeds used to repay unsecured debt principal	$ 204,800,000
6.250% senior unsecured notes
Debt Instrument [Line Items]
Senior unsecured notes, principal	$ 450,000,000				450,000,000	0
Debt instrument, stated rate	6.25%
Proceeds from issuance of debt, net of discount	$ 442,000,000
5.625% senior unsecured notes
Debt Instrument [Line Items]
Senior unsecured notes, principal					350,000,000	350,000,000				$ 350,000,000
Debt instrument, stated rate										5.625%
6.000% senior unsecured notes
Debt Instrument [Line Items]
Senior unsecured notes, principal					400,000,000	400,000,000			$ 400,000,000			$ 350,000,000
Debt instrument, stated rate									6.00%
7.875% Senior Unsecured Notes
Debt Instrument [Line Items]
Debt instrument, stated rate												7.875%
Note tender offer							300,100,000
Redemption premium							49,900,000
Loss on extinguishment of debt							$ 19,200,000
6.750% senior unsecured notes
Debt Instrument [Line Items]
Senior unsecured notes, principal				$ 750,000,000	750,000,000	750,000,000
6.750% senior unsecured notes \| Enterprise Offshore Acquisition [Member]
Debt Instrument [Line Items]
Debt instrument, stated rate				6.75%
Proceeds from issuance of debt, net of discount				$ 728,600,000
6.500% senior unsecured notes
Debt Instrument [Line Items]
Senior unsecured notes, principal					$ 550,000,000	$ 0
6.500% senior unsecured notes \| Alkali Business [Member]
Debt Instrument [Line Items]
Senior unsecured notes, principal		$ 550,000,000	$ 550,000,000
Debt instrument, stated rate		6.50%	6.50%
Proceeds from issuance of debt, net of discount		$ 540,100,000
Proceeds from issuance of unsecured debt			$ 540,100,000