Employee Benefit Plans - Stock Option Activity (Details) - Officer and Employee Plans [Member] - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Number
Shares, Outstanding	717,524	817,414
Shares, Exercised	(473,558)	(89,556)
Shares, Forfeited	(18,524)	(10,334)
Shares, Outstanding	225,442	717,524
Weighted Average Exercisable Price
Weighted Average Exercisable Price, Outstanding (in dollars per share)	$ 10.57	$ 10.62
Weighted Average Exercisable Price Exercised (in dollars per share)	9.61	8.98
Weighted Average Exercisable Price Forfeited (in dollars per share)	20.27	28.49
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 11.78	$ 10.57

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option 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)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-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.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Subparagraph (c)(1)(i)
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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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- Definition

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

+ References

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-SubTopic 10
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-Publisher SEC
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-Paragraph 29, 30
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