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.

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Shareholders' Equity - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Mar. 11, 2016
Stockholders Equity [Line items]
Capital conservation buffer rate	1.875%		1.25%
Stock Repurchase Program
Stockholders Equity [Line items]
Amount of stock authorized for repurchase				$ 100.0
Repurchase shares of common stock	243,000	0
Repurchase shares of common stock, value	$ 7.9