Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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Stock-Based Compensation (Details 4) - shares		1 Months Ended		3 Months Ended
Stock-Based Compensation (Details 4) - shares	May 05, 2017	Feb. 28, 2017	Jan. 31, 2017	Mar. 31, 2017
Nonvested share units
Stock-based compensation
Shares granted (in shares)				366,000
Time-Based \| Nonvested shares
Stock-based compensation
Shares granted (in shares)				91,000
Employee \| First Vesting Period \| Incentive Program Bonus Award Fiscal Year Performance \| Time-Based \| Nonvested shares
Stock-based compensation
Vesting (as a percent)		33.33%
Employee \| First Vesting Period \| Incentive Program Bonus Award Fiscal Year Performance \| Time-Based \| Nonvested share units
Stock-based compensation
Vesting (as a percent)		33.33%	33.33%
Employee \| Second Vesting Period \| Incentive Program Bonus Award Fiscal Year Performance \| Time-Based \| Nonvested shares
Stock-based compensation
Vesting (as a percent)		33.33%
Employee \| Second Vesting Period \| Incentive Program Bonus Award Fiscal Year Performance \| Time-Based \| Nonvested share units
Stock-based compensation
Vesting (as a percent)		33.33%	33.33%
Employee \| Third Vesting Period \| Incentive Program Bonus Award Fiscal Year Performance \| Time-Based \| Nonvested shares
Stock-based compensation
Vesting (as a percent)		33.33%
Employee \| Third Vesting Period \| Incentive Program Bonus Award Fiscal Year Performance \| Time-Based \| Nonvested share units
Stock-based compensation
Vesting (as a percent)		33.33%	33.33%
Subsequent Event \| Director \| Time-Based \| Nonvested share units
Stock-based compensation
Shares granted (in shares)	21,021
Subsequent Event \| Maximum \| Director \| Time-Based \| Nonvested share units
Stock-based compensation
Award vesting period	1 year