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Compensation Plans - Narrative (Detail) (USD $) |  |  |  | 9 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2014 | Dec. 31, 2013 | Sep. 30, 2014 2014 Equity and Cash Incentive Plan | Sep. 30, 2014 Restricted Stock Units (RSUs) | Sep. 30, 2014 401(K) Plan | Sep. 30, 2014 Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Deferred Compensation Equity | $ 11,453,744 | $ 11,397,560 |  |  |  |
Authorizes the issuance of Common Shares in various forms of equity awards |  |  | 600,000 |  |  |
Common shares available for issuance |  |  | 584,650 |  |  |
Deferred compensation related to unvested restricted stock grants |  |  |  | 11,453,744 |  |
Employee's compensation contributed to the plan |  |  |  |  | 6.00% |
Employer's compensation contributed to the plan |  |  |  |  | 200.00% |
Number of years of employment required to vest in contribution |  |  |  |  | 6 years |
Deferred Compensation Arrangement, Fully Vested Employee Elected Deferral Period |  |  |  |  |  | 5 years
Deferred Compensation Plan Assets | $ 4,000,000 |  |  |  |  |

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- Definition Value of stock issued under share-based plans to employees or officers which is the unearned portion, accounted for under the fair value method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415241&loc=d3e4534-113899 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.30) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount as of the balance sheet date of assets held under deferred compensation agreements. + 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 210.5-02.17) -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 17 -Article 5 + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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