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Debt - 7.5% Notes Due 2021 (Details) - Long-term Debt [Member] - Senior secured notes due June 01, 2021 [Member] - USD ($) | Jun. 04, 2013 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | ---
Debt Instrument [Line Items] |  |  |
Face amount | $ 250,000,000 |  |
Stated interest rate | 7.50% | 7.50% | 7.50%
Proceeds from debt issuance | $ 246,330,000 |  |
Fair value of debt instrument |  | $ 258,328,000 | $ 234,220,000
Equity interests in foreign subsidiaries, percentage |  | 65.00% |

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- Definition The debt instrument is secured by a pledge of and lien on 65% of equity interests in foreign subsidiaries or foreign holding companies directly owned by Century and the guarantors. + References No definition available. + Details
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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 + Details
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