Debt And Liquidity Debt And Liquidity (Senior Notes) (Details) - Senior Notes [Member] - USD ($)	Dec. 31, 2016	Nov. 20, 2012
Debt Instrument [Line Items]
Principal amount issued		$ 300,000,000
Stated interest rate		6.375%
Redemption price percentage of principal prior to November 15, 2016		100.00%
Repurchase percentage price of aggregate principal due to change in control		101.00%
Minimum [Member]
Debt Instrument [Line Items]
Unpaid indebtness after maturity or acceleration	$ 50,000,000
Unpaid judgment or decree	$ 50,000,000

Redemption Price Percentage Of Principal

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- Definition

Repurchase Percentage Price Of Aggregate Principal Due To Change In Control

+ References

No definition available.

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- Definition

Unpaid Indebtness After Maturity Or Acceleration

+ References

No definition available.

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- Definition

Unpaid Judgment Or Decree

+ References

No definition available.

+ Details

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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=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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