CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - shares	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017
Statement of Stockholders' Equity [Abstract]
Purchase of treasury shares, shares acquired (in shares)	614,454
Stock plan exercises; shares acquired (in shares)	12,971	24,672
Stock options exercised; shares issued (in shares)	52,404	106,351
Stock awards; shares issued (in shares)	7,774	6,034

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

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Balance Type:	na
Period Type:	duration