XML 95 R58.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2
5. Notes Payable and Long-Term Debt (Details) - USD ($)
Dec. 31, 2019
Apr. 30, 2019
Dec. 31, 2018
Dec. 31, 2010
Debt Instrument [Line Items]        
Debt and Lease Obligation $ 439,800,000   $ 439,400,000  
Other Long-term Debt, Current 426,200,000   500,000  
Long-term Debt and Lease Obligation 13,579,000   438,937,000  
Maturities of Long-term Debt [Abstract]        
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 426,800,000      
Long-term Debt, Maturities, Repayments of Principal in Year Two 1,600,000      
Long-term Debt, Maturities, Repayments of Principal in Year Three 1,500,000      
Long-term Debt, Maturities, Repayments of Principal in Year Four 400,000      
Long-term Debt, Maturities, Repayments of Principal in Year Five 400,000      
Long-term Debt, Maturities, Repayments of Principal after Year Five 9,700,000      
Line of Credit Facility, Remaining Borrowing Capacity 207,500,000      
Letters of Credit Outstanding, Amount 4,200,000      
Performance Guarantee [Member]        
Maturities of Long-term Debt [Abstract]        
Letters of Credit Outstanding, Amount 4,200,000      
Unsecured Debt [Member] | Senior Notes 4.875% due 2020 [Member]        
Debt Instrument [Line Items]        
Unsecured Debt 425,000,000.0   425,000,000.0  
Long-term debt 424,400,000   423,700,000 $ 422,600,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net 600,000   1,300,000  
Debt Instrument, Interest Rate, Effective Percentage       4.946%
Face amount of debt sold       $ 425,000,000.0
Debt Instrument, Interest Rate, Stated Percentage       4.875%
Finance Lease Obligations [Member] | Finance Leases and Other Debt [Member]        
Debt Instrument [Line Items]        
Other Long-term Debt 15,400,000   0  
Capital Lease Obligations [Member] | Capital Leases and Other Debt [Member]        
Debt Instrument [Line Items]        
Long-term Debt and Lease Obligation, Including Current Maturities 0   $ 15,700,000  
Line of Credit [Member]        
Maturities of Long-term Debt [Abstract]        
Line of Credit Facility, Maximum Borrowing Capacity   $ 200,000,000.0    
Long-term Line of Credit $ 0      
Line of Credit Facility, Interest Rate at Period End 3.035%      
Letters of Credit Outstanding, Amount $ 200,000