Share Repurchase Program - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	May 04, 2017	Feb. 12, 2015
Equity [Abstract]
Authorized share repurchase			$ 30,000,000	$ 20,000,000
Acquisition of treasury shares (in shares)	2,667,732	1,121,928
Value of shares repurchased	$ 25,598,000	$ 10,976,000
Cost per share acquired (in USD per share)	$ 9.60	$ 9.78

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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