v3.19.3.a.u2

Summary of Significant Accounting Policies - Additional Information (Details) |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2019 USD ($) | Dec. 31, 2019 USD ($) FinancialInstitution | Dec. 31, 2018 USD ($) FinancialInstitution | Dec. 31, 2017 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Unrealized loss on short-term investments |  | $ 17,000 | $ (17,000) | $ 0
Foreign currency gains (loss) |  | (200,000) | (500,000) | 100,000
Impairment of property and equipment |  |  | 400,000 | 0
Impairment to operating right of use assets |  | 900,000 |  |
Short-term investments |  | 0 | 42,146,000 |
Content related expenses |  | 1,700,000 |  |
Advertising costs |  | 7,300,000 | $ 3,000,000.0 | 3,400,000
Operating lease right-of-use assets | $ 39,900,000 | 283,291,000 |  |
Operating lease liability | 42,100,000 | $ 319,590,000 |  |
Reclassification of deferred and prepaid rents to right of use assets | $ 2,200,000 |  |  |
Maximum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Business combination measurement period from acquisition |  | 1 year |  |
Cash equivalents maturity period |  | 90 days |  |
Property and equipment, estimated useful lives |  | 5 years |  |
Minimum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Property and equipment, estimated useful lives |  | 18 months |  |
Customer 1 |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Number of financial institutions which manage cash balances | FinancialInstitution |  | 1 | 1 |
Customer 2 |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Number of financial institutions which manage cash balances | FinancialInstitution |  | 1 |  |
Cash, Cash Equivalents and Short-term Investment | Customer 1 |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Percentage of cash, cash equivalents balances |  | 65.00% | 97.00% |
Cash, Cash Equivalents and Short-term Investment | Customer 2 |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Percentage of cash, cash equivalents balances |  | 34.00% |  |
Website and Internal-Use Software |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Capitalized costs |  | $ 100,000 | $ 1,000,000.0 | 2,600,000
Amortized expenses |  | $ 1,600,000 | $ 2,000,000.0 | $ 1,100,000
Estimated useful life |  | 2 years |  |
Leasehold Improvements |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Property and equipment, estimated useful lives description |  | shorter of the lease term or their estimated useful lives, which range from five to ten years |  |
Leasehold Improvements | Maximum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Property and equipment, estimated useful lives |  | 10 years |  |
Leasehold Improvements | Minimum |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Property and equipment, estimated useful lives |  | 5 years |  |

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