Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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

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No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 210
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Equity Compensation Plans - Narrative (FY) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award
Stock options exercisable (shares)		293,296	228,392
Stock options exercised (shares)		0	0
Fair vale of options vested in period		$ 0.8	$ 1.3
Stock options granted (shares)		0
Dividend yield	0.00%		0.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Unrecognized compensation cost related to equity awards		$ 0.6
Period of recognition for unrecognized compensation costs (in years)		1 year 8 months 19 days
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Fair value of awards vested in period		$ 0.4	$ 0.1
Unrecognized compensation cost related to equity awards		$ 0.2
Period of recognition for unrecognized compensation costs (in years)		1 year
Performance Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Unrecognized compensation cost related to equity awards		$ 0.6
2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Common shares authorized for issuance (shares)		1,400,000
Common shares available for future grants (shares)		225,975
2012 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Options vesting period		1 year
2012 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Options vesting period		4 years
Term of options		10 years