XML 56 R46.htm IDEA: XBRL DOCUMENT
v3.25.2

Stock-Based Compensation - Schedule of Additional Information Regarding Stock Option Exercises (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Share-Based Payment Arrangement [Abstract] |  |  |  |
Intrinsic value of stock options exercised | $ 1 | $ 4 | $ 21 | $ 16
Cash received from option exercises | 5 | 9 | 46 | 24
Treasury shares repurchased for employee payroll taxes | (1) | (1) | (7) | (5)
Income tax benefit realized from option exercises | 1 | 1 | 3 | 4
Aggregate grant-date fair value of stock options vested | $ 0 | $ 0 | $ 16 | $ 15

X
- Definition Represents the aggregate grant-date fair value of stock options vested during the period. + References No definition available. + Details
Name: | unp_AggregateGrantDateFairValueOfStockOptionsVested
Namespace Prefix: | unp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Represents the amount of treasury shares repurchased for employee payroll taxes. + References No definition available. + Details
Name: | unp_TreasurySharesRepurchasedForEmployeePayrollTaxes
Namespace Prefix: | unp_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of tax benefit from exercise of option under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 2A -Subparagraph (a) -SubTopic 10 -Topic 718 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2A + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cash inflow from exercise of option under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 14 -Subparagraph (a) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-14 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 2A -Subparagraph (a) -SubTopic 10 -Topic 718 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2A + Details
Name: | us-gaap_ProceedsFromStockOptionsExercised
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration