Accounting Standards	6 Months Ended
Accounting Standards	Jul. 31, 2019
Accounting Policies [Abstract]
Accounting Standards	Accounting Standards Recently Adopted Accounting Pronouncements ASU No. 2016-02 In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842), which requires the recognition of right-of-use assets and lease liabilities on the balance sheet for those leases currently classified as operating leases under Accounting Standards Codification Topic 840 Leases. Accounting for finance leases remains substantially unchanged. We adopted this standard effective February 1, 2019, using a modified retrospective method, under which financial results reported in periods prior to February 1, 2019, were not adjusted. We elected the package of transition practical expedients, which among other things, does not require reassessment of lease classifications. Additionally, we elected to combine lease and non-lease components for each of our existing underlying asset classes and to not include leases with a term of 12 months or less on our condensed consolidated balance sheets. The most significant impact of adopting this standard was the recognition of $279 million of operating lease right-of-use assets and $307 million of operating lease liabilities on our condensed consolidated balance sheet as of February 1, 2019. Additionally, we reclassified $28 million in previously recognized deferred rent obligations and lease incentives to operating lease right-of-use assets. This adoption did not result in any cumulative-effect adjustments to Accumulated deficit, and there was no material impact on our condensed consolidated statement of operations. For further information, see Note 11, Leases. ASU No. 2017-12 In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815), to better align an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. We adopted this new standard effective February 1, 2019. As a result of adopting the standard, the entire change in the fair value of our foreign currency forward contracts designated as cash flow hedges will be presented in the same income statement line item as the respective hedged items. This adoption did not result in any cumulative-effect adjustments to Accumulated deficit, and the amended presentation guidance was applied prospectively. For further information, see Note 9, Derivative Instruments. ASU No. 2018-02 In February 2018, the FASB issued ASU No. 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, which provides entities the option to reclassify tax effects stranded in accumulated other comprehensive income as a result of the 2017 Tax Cuts and Jobs Act to retained earnings. We adopted this new standard effective February 1, 2019. The adoption of this new standard did not have a material impact on our condensed consolidated financial statements. ASU No. 2018-07 In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Non-employee Share-Based Payment Accounting, which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees, with certain exceptions. We adopted this standard effective February 1, 2019, and remeasured all outstanding equity-classified non-employee share-based payment awards at fair value as of the adoption date, which resulted in a $0.4 million cumulative-effect adjustment to Accumulated deficit. Recently Issued Accounting Pronouncements ASU No. 2016-13 In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the measurement and recognition of expected credit losses for financial assets held at amortized cost, including trade receivables. ASU No. 2016-13 replaces the existing incurred loss impairment model with an expected loss model that requires the use of forward-looking information to calculate credit loss estimates. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. These changes may result in more timely recognition of credit losses. We plan to adopt this new standard in the first quarter of our fiscal 2021. We are evaluating the accounting, transition, and disclosure requirements of this standard. The effect on our condensed consolidated financial statements will largely depend on the composition and credit quality of our investment portfolio and trade receivables as well as the economic conditions at the time of adoption.