XML 64 R51.htm IDEA: XBRL DOCUMENT
v3.20.1

Business and Summary of Significant Accounting Policies - Assumption Used to Estimate the Fair Value of Stock-Based Awards (Details) | 12 Months Ended
--- | ---
Jan. 31, 2020 | Jan. 31, 2019 | Jan. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expected dividends | 0.00% |  |
Performance Stock Unit |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of expected volatilities | 36.00% | 36.00% | 32.00%
Expected dividends | 0.00% | 0.00% | 0.00%
Range of risk-free interest rates | 2.50% | 2.00% |
Performance Stock Unit | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of risk-free interest rates |  |  | 1.00%
Performance Stock Unit | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of risk-free interest rates |  |  | 1.20%
Stock Option Plans |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expected dividends |  | 0.00% |
Stock Option Plans | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of expected volatilities |  | 37.00% |
Range of expected lives |  | 6 months |
Range of risk-free interest rates |  | 2.30% |
Stock Option Plans | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of expected volatilities |  | 42.00% |
Range of expected lives |  | 3 years 9 months |
Range of risk-free interest rates |  | 2.70% |
ESPP |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expected dividends | 0.00% | 0.00% | 0.00%
ESPP | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of expected volatilities | 33.00% | 33.00% | 31.00%
Range of expected lives | 6 months | 6 months | 6 months
Range of risk-free interest rates | 1.70% | 1.90% | 0.90%
ESPP | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Range of expected volatilities | 40.00% | 38.00% | 34.00%
Range of expected lives | 2 years | 2 years | 2 years
Range of risk-free interest rates | 2.50% | 2.80% | 1.40%

X
- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 + Details
Name: | us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_EmployeeStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |