Stock-Based Incentive Plans Nonvested Restricted Stock Units (Details) - $ / shares	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Awards, Restricted Stock Units, Vested Oustanding	60,000
Share-based Compensation Arrangement Restricted Stock Units, Nonvested	2,000	14,000
Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Nonvested, Weighted Average Grant Date Fair Value	$ 16.72	$ 16.27
Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Grants in Period	(12,000)
Granted	0
Nonvested at December 31, 2016	123,000	333,000
Granted, weighted average grant date fair value	$ 0.00
Vested, weighted average grant date fair value	16.18
Nonvested, weighted average grant date fair value at December 31, 2016	4.77	$ 8.90
Vested outstanding, weighted average grant date fair value	$ 15.38

Share-based Awards, Restricted Stock Units, Vested Oustanding

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- Definition

Share-based Compensation Arrangement Restricted Stock Units, Nonvested

+ References

No definition available.

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Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Nonvested, Weighted Average Grant Date Fair Value

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Vested During Period

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Vested in Period, Weighted Average Grant Date Fair Value

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Restricted Stock Units, Weighted Average Grant Date Fair Value

+ References

No definition available.

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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

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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

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

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.

+ References

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