Aggregate number of common shares reserved for future issuance.

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 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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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

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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 (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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).

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Shareholders' Equity - Plan Summary and Description (Details) - shares	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restricted Stock
Information pertaining to stock based awards
Outstanding awards issued (in shares)	1,200,000	1,400,000	1,500,000	1,400,000
RSUs
Information pertaining to stock based awards
Outstanding awards issued (in shares)	1,200,000	700,000	800,000	700,000
SSAR Awards
Information pertaining to stock based awards
Outstanding awards issued (in shares)	300,000	200,000	200,000	200,000
2016 Plan
Information pertaining to stock based awards
Common stock authorized for issuance (in shares)	2,500,000
Remaining shares of common stock available for future issuance (in shares)	4,300,000
2016 Plan \| Restricted Stock
Information pertaining to stock based awards
Outstanding awards issued (in shares)	0
2016 Plan \| RSUs
Information pertaining to stock based awards
Outstanding awards issued (in shares)	0
2016 Plan \| SSAR Awards
Information pertaining to stock based awards
Outstanding awards issued (in shares)	0
2006 Plan
Information pertaining to stock based awards
Common stock subject to outstanding awards (in shares)	3,108,258
Remaining shares of common stock available for future issuance (in shares)	0
2006 Plan \| Restricted Stock
Information pertaining to stock based awards
Outstanding awards issued (in shares)	1,200,000
2006 Plan \| RSUs
Information pertaining to stock based awards
Outstanding awards issued (in shares)	1,200,000
2006 Plan \| SSAR Awards
Information pertaining to stock based awards
Outstanding awards issued (in shares)	300,000