Annual report pursuant to Section 13 and 15(d)

Acquisitions Acquisitions - Pro Forma Results (Details)

v3.19.1
Acquisitions Acquisitions - Pro Forma Results (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
1 Months Ended 12 Months Ended
Apr. 19, 2017
Apr. 19, 2017
Mar. 31, 2019
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Components of the Acquisition Price [Abstract]            
Pro forma revenues (3)       $ 1,217,655 $ 1,060,777  
Pro forma net income from continuing operations available to common stockholders (3)       $ 51,975 $ 226,086  
Pro forma earnings per common share - basic (in dollars per share)       $ 0.98 $ 4.86  
Pro forma earnings per common share - diluted (in dollars per share)       $ 0.89 $ 4.08  
Pro forma common shares - basic (in shares)     57,840 52,798 46,552  
Pro forma common shares - diluted (in shares)     59,082 58,640 55,389  
Business Acquisition [Line Items]            
Equity income (loss) from equity method investments   $ 76,192 $ (3,304) $ 76,192 $ 41,643  
Business combination bargain purchase, gain recognized     $ 0 130,880 0  
TOKIN            
Business Acquisition [Line Items]            
Remeasurement gain (loss)       $ 68,700 66,700  
Business combination bargain purchase, gain recognized $ 62,159       60,300  
NEC TOKIN Corporation            
Business Acquisition [Line Items]            
Equity income (loss) from equity method investments   $ 75,177     $ 41,643  
NEC TOKIN Corporation | Stock Purchase Agreement | KEMET Electronics Corporation            
Business Acquisition [Line Items]            
Ownership percentage 34.00% 34.00%   34.00% 34.00% 34.00%
TOKIN            
Business Acquisition [Line Items]            
Equity income (loss) from equity method investments   $ 75,200   $ 123,400