Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Stockholders' Equity
Other comprehensive income (loss), tax	$ 179	$ (412)	$ 144
Cash dividends (in dollars per share)	$ 0.48	$ 0.48	$ 0.48
Issuance of common stock - unvested shares (in shares)	7,333	3,984	23,704
Issuance of common stock - vested shares (in shares)	4,194	5,139	4,536
Repurchase of common stock (in shares)	368	382	3,661

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern 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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