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.

No definition available.

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

Description of the estimated period of time over which an employee may exercise the vested equity compensation award granted. This period may be explicit or implicit based on the terms of the award, and may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

No definition available.

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Equity Compensation Plans - Summary of Equity Awards Granted (Details) - shares			6 Months Ended	12 Months Ended
	Apr. 16, 2018	Apr. 01, 2018	Jun. 30, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Stock (in shares)			885,818
Units (in shares)			1,369,268	1,125,004
Stock options
Class of Stock [Line Items]
Stock (in shares)			885,818
Stock options \| Four-year graded vesting
Class of Stock [Line Items]
Stock (in shares)	11,491	873,383	944
Stock options \| Three-year cliff vesting
Class of Stock [Line Items]
Stock (in shares)		0
Restricted stock
Class of Stock [Line Items]
Stock (in shares)			189,994
Units (in shares)			167,072	143,557
Restricted stock \| Four-year graded vesting
Class of Stock [Line Items]
Stock (in shares)	2,338	187,462	194
Restricted stock \| Three-year cliff vesting
Class of Stock [Line Items]
Stock (in shares)		0
Performance shares
Class of Stock [Line Items]
Units (in shares)			46,705
Performance shares \| Four-year graded vesting
Class of Stock [Line Items]
Units (in shares)	0	0	0
Performance shares \| Three-year cliff vesting
Class of Stock [Line Items]
Units (in shares)		46,705
January 1 to June 30, 2018 \| Four-year graded vesting
Class of Stock [Line Items]
Equity award contractual term (in years)			4 years
April 1, 2018 \| Four-year graded vesting
Class of Stock [Line Items]
Equity award contractual term (in years)		4 years
April 1, 2018 \| Three-year cliff vesting
Class of Stock [Line Items]
Equity award contractual term (in years)		3 years
April 16, 2018 \| Four-year graded vesting
Class of Stock [Line Items]
Equity award contractual term (in years)			4 years