v3.19.1

Share-Based Compensation - Nonvested Options (Details)	12 Months Ended
	Dec. 31, 2018 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Unvested Options, Outstanding at beginning of period (in shares) | shares	578,154
Unvested Options, Granted (in shares) | shares	110,000
Unvested Options, Vested (in shares) | shares	(323,553)
Unvested Options, Forfeited (in shares) | shares	(17,327)
Unvested Options, Outstanding at end of period (in shares) | shares	347,274
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-Average Exercise Price Per Share, Outstanding (in dollars per share) | $ / shares	$ 9.96
Weighted-Average Exercise Price Per Share, Granted (in dollars per share) | $ / shares	15.36
Weighted-Average Exercise Price Per Share, Vested (in dollars per share) | $ / shares	9.41
Weighted-Average Exercise Price Per Share, Forfeited (in dollars per share) | $ / shares	10.24
Weighted-Average Exercise Price Per Share, Outstanding (in dollars per share) | $ / shares	$ 12.17

X

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

X

- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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Period Type:	duration

X

- Definition

Number of non-vested options outstanding.

+ References

No definition available.

+ Details

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X

- 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.

+ Details

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X

- Definition

Number of non-vested options forfeited.

+ References

No definition available.

+ Details

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X

- Definition

Weighted average grant-date fair value of non-vested options forfeited.

+ References

No definition available.

+ Details

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

+ References

No definition available.

+ Details

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- References

No definition available.

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X

- Definition

Number of options vested.

+ References

No definition available.

+ Details

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X

- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

+ Details

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