v3.8.0.1

Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Mar. 31, 2016
Amortizable Intangible Assets |  |  |
Useful life of capitalized content development costs | 5 years |  |
Non-Cash Long-Lived Asset Additions |  |  |
Capital asset additions during the period | $ 62.3 | $ 30.8 |
Minimum |  |  |
Amortizable Intangible Assets |  |  |
Estimated useful life of intangible assets (in years) | 3 years |  |
Maximum |  |  |
Amortizable Intangible Assets |  |  |
Estimated useful life of intangible assets (in years) | 10 years |  |
Accounts payable and accrued expenses |  |  |
Marketing and Sales Costs |  |  |
Accrued marketing costs | $ 11.7 | 5.6 |
ASU 2016-09 |  |  |
Recent Accounting Pronouncements |  |  |
Amount of cumulative-effect reduction to retained earnings with an offset to additional paid-in-capital |  |  | $ (0.1)
Computer hardware | Minimum |  |  |
Property and Equipment, Net |  |  |
Useful lives (in years) | 3 years |  |
Computer hardware | Maximum |  |  |
Property and Equipment, Net |  |  |
Useful lives (in years) | 5 years |  |
Furniture and office equipment | Minimum |  |  |
Property and Equipment, Net |  |  |
Useful lives (in years) | 5 years |  |
Furniture and office equipment | Maximum |  |  |
Property and Equipment, Net |  |  |
Useful lives (in years) | 7 years |  |
Leasehold improvements | Minimum |  |  |
Property and Equipment, Net |  |  |
Useful lives (in years) | 4 years |  |
Leasehold improvements | Maximum |  |  |
Property and Equipment, Net |  |  |
Useful lives (in years) | 11 years |  |
Internally-developed software |  |  |
Amortizable Intangible Assets |  |  |
Estimated useful life of intangible assets (in years) | 3 years |  |
Landlord funded leasehold improvements |  |  |
Non-Cash Long-Lived Asset Additions |  |  |
Non-cash capital expenditure | $ 11.2 | 6.4 |
Graduate Program Segment | Minimum |  |  |
Revenue by segment |  |  |
Term of revenue contracts | 10 years |  |
Graduate Program Segment | Maximum |  |  |
Revenue by segment |  |  |
Term of revenue contracts | 15 years |  |
Short Course Segment |  |  |
Revenue by segment |  |  |
Allowance for Doubtful Accounts Receivable | $ 0.3 | $ 0.0 |

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