Stock and Incentive Compensation Plans - Summary of Stock Plan Activity (Details) - Stock and Incentive Compensation Plan [Member] - shares	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018
Performance Based Award [Member]
Shares [Roll Forward]
Nonvested shares, beginning of period (in shares)	185,920	213,516
Granted (in shares)		51,174
Released from restriction (in shares)	(1,207)	(55,351)
Forfeited (in shares)	(7,018)	(31,644)
Nonvested shares, end of period (in shares)	177,695	177,695
Time-Vested Awards [Member]
Shares [Roll Forward]
Nonvested shares, beginning of period (in shares)	337,910	320,357
Granted (in shares)	500	116,825
Released from restriction (in shares)	(8,388)	(106,780)
Forfeited (in shares)	(7,494)	(7,874)
Nonvested shares, end of period (in shares)	322,528	322,528

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

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://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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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
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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.

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting 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)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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