Earnings Per Common Share - Share repurchase activities (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares
Earnings Per Common Share
Average price paid per share in share repurchase program \| $ / shares	$ 7.04
Approximate dollar value of shares that may yet be purchased under the plans or programs	$ 15.0
Value of shares repurchased under program	$ 1.3

Amount remaining of a stock repurchase plan authorized.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant