Consolidated Balance Sheet (Parenthetical) - $ / shares	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Preferred Stock, Shares Authorized	5,000,000	5,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	90,000,000	90,000,000
Common Stock, Shares, Issued	22,471,705	22,393,537
Common Stock, Shares, Outstanding	16,234,603	16,773,586
Treasury Stock, Shares	6,237,102	5,619,951