XML 88 R68.htm IDEA: XBRL DOCUMENT v3.6.0.2
Senior Notes, Convertible Notes and Trust Preferred Securities - Schedule of Long-term Debt Instruments (Details) - USD ($)
Dec. 31, 2016
Dec. 31, 2015
May 31, 2014
Jun. 30, 2013
Debt Instrument [Line Items]        
Unamortized debt issuance costs $ (7,126,000)      
Senior Notes [Member]        
Debt Instrument [Line Items]        
Principal amount of debt component 500,000,000 $ 500,000,000    
Unamortized discount (1,780,000) (2,053,000)    
Unamortized debt issuance costs (3,858,000) (4,421,000)    
Long-term debt 494,362,000 493,526,000    
Senior Notes [Member] | Senior Notes Due 2024 [Member]        
Debt Instrument [Line Items]        
Principal amount of debt component $ 250,000,000 $ 250,000,000    
Debt interest rate percentage 4.40% 4.40% 4.40%  
Issue Price 99.883%      
Senior Notes [Member] | Senior Notes Due 2023 [Member]        
Debt Instrument [Line Items]        
Principal amount of debt component $ 250,000,000 $ 250,000,000    
Debt interest rate percentage 4.25% 4.25%   4.25%
Issue Price 99.026%