v3.3.0.814
DEBT (Details)
3 Months Ended 6 Months Ended
Nov. 05, 2015
USD ($)
Aug. 13, 2015
USD ($)
Jul. 13, 2015
USD ($)
Sep. 30, 2015
USD ($)
Sep. 30, 2014
USD ($)
Sep. 30, 2015
USD ($)
Sep. 30, 2014
USD ($)
Aug. 14, 2015
USD ($)
Jun. 30, 2015
USD ($)
Apr. 17, 2015
USD ($)
Mar. 31, 2015
USD ($)
Debt Instrument [Line Items]                      
Total debt       $ 1,003,380,000   $ 1,003,380,000         $ 864,422,000
Less short-term borrowings and current maturities of long-term debt       (30,041,000)   (30,041,000)         (18,730,000)
Total long-term debt       $ 973,339,000   973,339,000         845,692,000
Proceeds from borrowings           461,581,000 $ 219,354,000        
Long Term Convertible Debt Current And Noncurrent [Abstract]                      
Amortization of debt discount           $ 946,000 2,130,000        
Term Loan and Revolving Credit Facility                      
Debt Instrument [Line Items]                      
Debt Instrument Required Leverage Ratio Numerator, Maximum       4   4          
Debt Instrument Required Leverage Ratio Denominator       1   1          
Debt Instrument Required Coverage Ratio Numerator, Minimum       2.75   2.75          
Debt Instrument Required Coverage Ratio Denominator       1   1          
Sixth amendment | Term Loan and Revolving Credit Facility                      
Debt Instrument [Line Items]                      
Debt Instrument Required Leverage Ratio Numerator, Maximum, Period One       4.75   4.75          
Debt Instrument Required Leverage Ratio Denominator Period One       1   1          
Debt Instrument Required Leverage Ratio Numerator, Maximum, Period Two       4.5   4.5          
Debt Instrument Required Leverage Ratio Denominator Period Two       1   1          
Debt Instrument Required Leverage Ratio Numerator, Maximum, Period Three       4.25   4.25          
Debt Instrument Required Leverage Ratio Denominator Period Three       1   1          
Debt Instrument Required Leverage Ratio Numerator, Maximum, Period Four       4.0   4.0          
Debt Instrument Required Leverage Ratio Denominator Period Four       1   1          
Debt Instrument Required Coverage Ratio Numerator, Minimum, Period One       2.0   2.0          
Debt Instrument Required Coverage Ratio Denominator, Period One       1   1          
Debt Instrument Required Coverage Ratio Numerator, Minimum, Period Two       2.25   2.25          
Debt Instrument Required Coverage Ratio Denominator, Period Two       1   1          
Debt Instrument Required Coverage Ratio Numerator, Minimum, Period Three       2.5   2.5          
Debt Instrument Required Coverage Ratio Denominator, Period Three       1   1          
Debt Instrument Required Coverage Ratio Numerator, Minimum, Period Four       2.75   2.75          
Debt Instrument Required Coverage Ratio Denominator, Period Four       1   1          
Trigger Point, Maximum Leverage Ratio Numerator Amount       4.25   4.25          
Trigger Point, Leverage Ratio Denominator Amount       1   1          
Senior Notes | Senior Notes Due 2022                      
Debt Instrument [Line Items]                      
Total debt       $ 401,535,000   $ 401,535,000         401,535,000
Debt instrument, interest rate, stated percentage       6.25%   6.25%          
Senior Notes | Senior Notes Due 2022 | Quarter To Date                      
Debt Instrument [Line Items]                      
Debt instrument, repurchase amount         $ 20,000,000   20,000,000        
Senior Notes | Senior Notes Due 2022 | Year To Date                      
Debt Instrument [Line Items]                      
Debt instrument, repurchase amount         31,200,000   31,200,000        
Term Loan                      
Debt Instrument [Line Items]                      
Total debt       $ 342,611,000   $ 342,611,000       $ 222,600,000 222,179,000
Repayment of debt           7,000,000          
Term Loan | Fifth amendment                      
Debt Instrument [Line Items]                      
Total debt                   350,000,000  
Term Loan | $200 million Term Loan | Subsequent event                      
Debt Instrument [Line Items]                      
Debt instrument, face amount $ 200,000,000                    
Debt instrument, interest rate, stated percentage 2.00%                    
Percentage of domestic capital stock guarantee 100.00%                    
Percentage of foreign capital stock guarantee 65.00%                    
Revolving Credit Facility                      
Debt Instrument [Line Items]                      
Total debt       223,800,000   223,800,000         83,800,000
Debt instrument, face amount                   350,000,000  
Proceeds from borrowings           334,200,000          
Repayment of debt           194,200,000          
Letters of credit outstanding amount       600,000   600,000          
Revolving Credit Facility | Fifth amendment                      
Debt Instrument [Line Items]                      
Debt instrument, face amount                   $ 400,000,000  
Other debt | Convertible Senior Notes Due 2038                      
Debt Instrument [Line Items]                      
Total debt     $ 1,900,000 0   0         114,109,000
Debt instrument, face amount       0   0         115,000,000
Debt instrument, repurchase amount               $ 1,900,000 $ 113,100,000    
Debt Instrument, redemption price, percentage of principal amount redeemed     100.00%                
Debt instrument, convertible, conversion ratio   13.8373                  
Per principal amount of convertible debt   $ 1,000                  
Debt instrument, interest rate, stated percentage                 3.00%    
Long Term Convertible Debt Current And Noncurrent [Abstract]                      
Equity component- net carrying value       14,905,000   14,905,000         14,905,000
Debt component- unamortized discount       0   0         (891,000)
Contractual coupon interest       7,000 863,000 725,000 1,726,000        
Amortization of debt discount       0 1,048,000 891,000 2,067,000        
Total interest expense       $ 7,000 $ 1,911,000 $ 1,616,000 $ 3,793,000        
Other debt | Convertible Senior Notes Due 2038 | Quarter To Date                      
Long Term Convertible Debt Current And Noncurrent [Abstract]                      
Debt Instrument, Convertible, Effective Interest Rate         6.90%   6.90%        
Other debt | Convertible Senior Notes Due 2038 | Year To Date                      
Long Term Convertible Debt Current And Noncurrent [Abstract]                      
Debt Instrument, Convertible, Effective Interest Rate       6.90% 6.90% 6.90% 6.90%        
Other debt | Airnorth                      
Debt Instrument [Line Items]                      
Total debt       $ 20,839,000   $ 20,839,000         23,119,000
Other debt | Eastern Airways                      
Debt Instrument [Line Items]                      
Total debt       $ 14,595,000   $ 14,595,000         $ 19,680,000