Annual report pursuant to Section 13 and 15(d)

Debt (Senior Credit Facility) (Details)

v3.10.0.1
Debt (Senior Credit Facility) (Details)
 12 Months Ended
Dec. 31, 2018
USD ($)
Term Loan | Term Loan B  
Line of Credit Facility [Line Items]  
Line of credit availability $ 240,700,000.0
Basis spread on variable rate (as a percent) 2.25%
Principal payments, a percentage of the original principal amount 0.25%
Line of credit, outstanding balance $ 240,100,000
Term Loan | Term Loan A  
Line of Credit Facility [Line Items]  
Total leverage ratio 6.50
Secured leverage ratio 4.00
Senior credit facility  
Line of Credit Facility [Line Items]  
Remainder amount available for borrowing $ 64,900,000
Senior credit facility | Revolving Credit Facility  
Line of Credit Facility [Line Items]  
Line of credit availability 550,000,000.0
Line of credit, outstanding balance $ 475,000,000
Senior credit facility | Revolving Credit Facility | LIBOR | Minimum  
Line of Credit Facility [Line Items]  
Basis spread on variable rate (as a percent) 1.50%
Senior credit facility | Revolving Credit Facility | LIBOR | Maximum  
Line of Credit Facility [Line Items]  
Basis spread on variable rate (as a percent) 2.75%
Senior credit facility | Letters of Credit  
Line of Credit Facility [Line Items]  
Line of credit, outstanding balance $ 10,100,000