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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

X

- Definition

Deferred Compensation Arrangement, Fully Vested Employee Elected Deferral Period

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- Definition

Number years of service required of employees to vest in contribution.

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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

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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

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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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

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 718

-SubTopic 10

-Section 50

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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-Publisher FASB

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-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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