XML 80 R61.htm IDEA: XBRL DOCUMENT v3.20.2
Other long-term liabilities - Schedule of Long-Term Liabilities and Deferred Credits (Detail) - USD ($)
$ in Thousands
Jun. 30, 2020
Dec. 31, 2019
Other Long-term Liabilities    
Advances in aid of construction $ 62,664 $ 60,828
Environmental remediation obligation 66,446 58,061
Asset retirement obligations 54,794 53,879
Customer deposits 31,708 31,946
Unamortized investment tax credits 18,051 18,234
Deferred credits 18,856 18,952
Contingent development support obligations 10,898 9,446
Preferred shares, Series C 12,975 13,793
Lease liabilities 14,248 9,695
Other 29,293 26,506
Other long-term liabilities 319,933 301,340
Less: current portion (56,944) (57,939)
Other long-term liabilities, excluding current $ 262,989 $ 243,401