Intangible Assets and Goodwill - Summary of Methodology Used in Valuation of FCC Licenses (Details)	Feb. 28, 2018	Feb. 28, 2017	Feb. 29, 2016
Maximum | Discount Rate
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	12.3	12.4	12.5
Maximum | Long-term Revenue Growth Rate
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	1.0	1.8	2.0
Maximum | Mature Market Share
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	30.2	31.1	30.4
Maximum | Operating Profit Margin
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	38.0	39.1	39.1
Minimum | Discount Rate
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	11.9	12.1	12.2
Minimum | Long-term Revenue Growth Rate
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	0.3	1.0	1.0
Minimum | Mature Market Share
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	12.9	12.7	3.1
Minimum | Operating Profit Margin
Goodwill And Other Intangibles [Line Items]
FCC license valuation assumptions	26.0	27.0	25.1