XML 89 R71.htm IDEA: XBRL DOCUMENT v3.20.2
Financing Arrangements - Underwritten Public Offering (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Dec. 31, 2018
Sep. 30, 2019
Sep. 30, 2020
Financing Arrangements      
Stock issued under equity offering, net (in shares) 3,795,000 3,795,000  
Stock offering price (per share) $ 60.00    
Proceeds from equity offering, net $ 215,800 $ 215,832  
Underwriting discounts and commissions and offering expenses $ 11,900    
Self-insurance liabilities   $ 7,400 $ 5,100