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.

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

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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 options outstanding, including both vested and non-vested options.

+ 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

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

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Compensation Plans - Summary of Outstanding Equity Awards (Details) - shares	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	157,201	217,873	469,289	486,563
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	1,287,915	1,095,305	1,582,062	2,322,438
Leadership grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	356,242	405,826	290,536	173,271
Amended And Restated 2003 Annual And Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	157,201
Amended And Restated 2003 Annual And Long-Term Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	1,287,915
Amended And Restated 2003 Annual And Long-Term Incentive Plan \| Sign On Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	355,538
Amended And Restated 2003 Annual And Long-Term Incentive Plan \| Annual Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	932,377
Amended And Restated 2003 Annual And Long-Term Incentive Plan \| Leadership grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock or units outstanding	356,242