Earnings (Loss) Per Common Share (Narrative) (Details) - $ / shares	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
3.875% Convertible Senior Debentures, due November 1, 2029 [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Convertible notes interest rate	3.875%	3.875%	3.875%
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share amount	4,000,000	4,000,000	4,000,000
Exercise price	$ 33.33	$ 33.33	$ 33.33
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share amount	1,000,137	1,572,777	1,711,096
Redeemable Convertible Preferred Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share amount	4,162,200	4,162,200

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

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