Benefit Plans - Activity (Details)	6 Months Ended
Jun. 30, 2016 $ / shares shares
Restricted Stock Awards
Awards/Units Outstanding (in shares)
Balance at beginning of period \| shares	27,529
Granted \| shares	10,232
Vested \| shares	(18,815)
Balance at end of period \| shares	18,946
Weighted-Average Grant Date Fair Value Per Share (in dollars per share)
Balance at beginning of period \| $ / shares	$ 18.17
Granted \| $ / shares	24.44
Vested \| $ / shares	19.94
Balance at end of period \| $ / shares	$ 19.81
Deferred Stock Units
Awards/Units Outstanding (in shares)
Balance at beginning of period \| shares	0
Granted \| shares	5
Vested \| shares	(5)
Balance at end of period \| shares	0
Weighted-Average Grant Date Fair Value Per Share (in dollars per share)
Balance at beginning of period \| $ / shares	$ 0.00
Granted \| $ / shares	24.10
Vested \| $ / shares	24.10
Balance at end of period \| $ / shares	$ 0.00
Restricted Stock Units
Awards/Units Outstanding (in shares)
Balance at beginning of period \| shares	28,302
Granted \| shares	30,704
Vested \| shares	(9,470)
Balance at end of period \| shares	49,536
Weighted-Average Grant Date Fair Value Per Share (in dollars per share)
Balance at beginning of period \| $ / shares	$ 18.90
Granted \| $ / shares	25.63
Vested \| $ / shares	18.92
Balance at end of period \| $ / shares	$ 23.07

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).

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

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 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

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+ 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://www.xbrl.org/2003/role/presentationRef
-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=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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