Stock-Based Compensation (Restricted stock award) (Details)_new - Restricted Stock [Member] - C3J Stock Plan 2016 [Member] - $ / shares	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Shares
Outstanding at beginning of period (in shares)	416,856
Forfeited/Cancelled (in shares)	(32,714)
Outstanding at end of period (in shares)	355,034	416,856
Weighted Avg Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 29.17
Outstanding at end of period (in dollars per share)	$ 29.25	$ 29.17
C3J [Member]
Shares
Outstanding at beginning of period (in shares)	416,871	420,883	436,742
Granted (in shares)		16,895	493
Forfeited/Cancelled (in shares)		(20,907)	(16,352)
Outstanding at end of period (in shares)		416,871	420,883
Weighted Avg Grant Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 29.19	$ 29.80	$ 29.80
Granted (in dollar per share)		9.73	25.14
Forfeited/Cancelled, Weighted Avg Grant Date Fair Value		25.75	31.02
Outstanding at end of period (in dollars per share)		$ 29.19	$ 29.80

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

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)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&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

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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.

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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

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-Topic 718
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-Paragraph 2
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