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

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-Publisher FASB
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
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Balance Type:
Period Type:

Debt (6.625% Senior Notes) (Details) - USD ($)		12 Months Ended
Debt (6.625% Senior Notes) (Details) - USD ($)	Apr. 18, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 19, 2013	Feb. 10, 2011
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ 0	$ 0	$ 15,885,000
Senior Notes \| 6.625% Senior Notes
Debt Instrument [Line Items]
Stated interest rate		6.625%	6.625%		6.00%	6.625%
Debt instrument, face amount						$ 300,000,000
Repurchase amount	$ 231,000,000
Loss on extinguishment of debt	$ 15,900,000