XML 68 R58.htm IDEA: XBRL DOCUMENT
v3.21.2

Share Repurchase Program (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended | 10 Months Ended | 177 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Oct. 20, 2021 | Jun. 30, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | [3] | Sep. 30, 2020 | Mar. 31, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020 | Sep. 30, 2021 | Apr. 01, 2019
Shares Repurchased [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
BOD authorized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 150,000,000
Stock repurchase program expiration date |  |  |  |  |  |  |  |  |  |  |  |  | Mar. 31, 2022 |  |  |  |
Aggregate cost |  |  |  | $ 1,409 |  |  |  |  |  |  |  |  | $ 5,926 | $ 2,956 |  | $ 46,800 |
Shares repurchased |  |  |  | 8,604,239 | [1] | 12,204,409 | [2] | 6,691,421 | 4,045,575 | [1] | 14,305,793 | [3] | 27,500,069 | 18,351,368 |  |  |
Average purchase price | [4] |  |  | $ 210.31 | [1] | $ 222.46 | [2] | $ 209.50 | $ 98.87 | [1] | $ 178.66 | [3] | $ 215.51 | $ 161.07 |  |  |
Remaining number of shares that may be repurchased under current authority |  |  |  | 83,522,901 |  |  |  |  |  |  |  |  | 83,522,901 |  |  | 83,522,901 |
Treasury stock, value |  |  |  | $ 46,372 |  |  |  |  |  |  |  |  | $ 46,372 |  | $ 40,420 | $ 46,372 |
Accelerated Share Repurchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Repurchased [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate cost |  |  | $ 2,000 |  |  |  |  |  |  |  |  |  |  |  | $ 2,000 |  |
Shares repurchased |  |  | 7,209,156 | 1,983,859 |  | 7,209,156 |  |  | 4,045,575 |  | 8,786,380 |  |  |  | 8,786,380 |  |
Average purchase price |  |  |  |  |  |  |  |  |  |  |  |  | $ 217.56 | $ 155.86 |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Repurchased [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate cost |  | $ 405 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares repurchased |  | 1,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | Includes an incremental 1,983,859 and 4,045,575 shares received upon final settlement in September 2021 and July 2020, respectively, under accelerated share repurchase programs.
[2] | Includes 7,209,156 shares repurchased in May 2021 under accelerated share repurchase programs.
[3] | Includes 8,786,380 shares repurchased in February 2020 under accelerated share repurchase programs.
[4] | In the period of the final settlement, the average price paid under the accelerated share repurchase programs is calculated based on the total program value less the value assigned to the initial delivery of shares. The average price of the completed 2021 and 2020 accelerated share repurchase programs was $217.56 and $155.86, respectively.

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_EquityClassOfTreasuryStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramExpirationDate
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockAcquiredAverageCostPerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_TreasuryStockSharesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29,30) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770 + Details
Name: | us-gaap_TreasuryStockValueAcquiredCostMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_AcceleratedShareRepurchasesDateAxis=unp_AcceleratedShareRepurchaseAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |