The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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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- 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

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

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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

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Period Type:	duration

- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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

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Share-Based Compensation - Summary of Restricted Share and Restricted Stock Unit Activity (Details) - $ / shares					12 Months Ended
	Jun. 15, 2016	Jan. 26, 2016	Jun. 16, 2015	Jan. 28, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Shares
Unvested, Beginning (in shares)						0	130,914
Granted (in shares)							4,000
Vested (in shares)							(134,914)
Unvested, Ending (in shares)							0
Weighted Average Grant Date Fair Value
Unvested Shares, Weighted Average Grant Date Fair Value (in dollars per share)							$ 0.00	$ 20.70
Granted (in dollars per share)					$ 0.00		23.46
Vested (in dollars per share)							$ 25.79
Restricted shares
Number of Shares
Unvested, Beginning (in shares)					776,456	710,182	0
Granted (in shares)	31,167	136,623	34,587	126,319	167,790	160,906	713,727
Vested (in shares)					(191,498)	(86,517)	(3,545)
Forfeited (in shares)					(539)	(8,115)
Unvested, Ending (in shares)					752,209	776,456	710,182
Weighted Average Grant Date Fair Value
Unvested Shares, Weighted Average Grant Date Fair Value (in dollars per share)								0.00
Granted (in dollars per share)		$ 26.93		$ 26.58	$ 27.29	$ 26.46	$ 26.66
Vested (in dollars per share)					26.54	26.02	$ 26.66
Forfeited (in dollars per share)					$ 26.82	$ 26.64
Restricted stock units
Number of Shares
Unvested, Beginning (in shares)					1,884,110	1,266,237	0
Granted (in shares)		277,386		256,467
Vested (in shares)					0	0	0
Forfeited (in shares)					(2,727)	(21,377)
Unvested, Ending (in shares)					2,572,768	1,884,110	1,266,237
Weighted Average Grant Date Fair Value
Unvested Shares, Weighted Average Grant Date Fair Value (in dollars per share)								$ 0.00
Vested (in dollars per share)					$ 0.00	$ 0.00	$ 0.00
Forfeited (in dollars per share)					15.54	15.80
Restricted stock units, maximum
Number of Shares
Granted (in shares)		691,385		639,250			1,266,237
Weighted Average Grant Date Fair Value
Granted (in dollars per share)					$ 15.57	$ 15.47	$ 15.99