What was the change in total debt between 2018 and 2019?
{"Term loans": {"2019": 756060, "2018": 284959}, "Revolving credit facility": {"2019": 239000, "2018": "\u2014"}, "5.750% Senior Notes, due August 2026": {"2019": 400000, "2018": 400000}, "Debt issuance costs": {"2019": -21905, "2018": -13203}, "Total debt": {"2019": 1373155, "2018": 671756}, "Less current portion of term credit facility": {"2019": 38950, "2018": 23747}, "Less current portion of debt issuance costs": {"2019": -4802, "2018": -2980}, "Total long-term debt": {"2019": 1339007, "2018": 650989}}
total_debt_2019 = df["Total debt"]["2019"]
total_debt_2018 = df["Total debt"]["2018"]
answer = total_debt_2019 - total_debt_2018