Quarterly report pursuant to Section 13 or 15(d)

Condensed Consolidated Balance Sheets (Parenthetical)

v3.8.0.1
Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)
shares in Thousands, $ in Thousands
Mar. 31, 2018
Dec. 31, 2017
Mar. 31, 2017
Allowance for doubtful accounts $ 7,696 $ 9,043 $ 7,726
Accumulated depreciation for property, plant and equipment $ 467,047 $ 455,811 $ 421,809
Preferred stock, shares authorized (in shares) 10,000 10,000 10,000
Preferred stock, shares issued (in shares) 0 0 0
Preferred stock, shares outstanding (in shares) 0 0 0
Common stock, no par value (in dollars per share) $ 0 $ 0 $ 0
Common stock, shares authorized (in shares) 125,000 125,000 125,000
Common stock, shares issued (in shares) 70,113 69,995 69,634
Common stock, shares outstanding (in shares) 70,113 69,995 69,634