v2.4.1.9

Treasury Stock - Additional Information (Detail) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013
Equity, Class of Treasury Stock [Line Items] |  |
Treasury stock, shares | 6,405,000us-gaap_TreasuryStockShares | 6,405,000us-gaap_TreasuryStockShares
Treasury stock, cost | 475,184,000us-gaap_TreasuryStockValue | $ 475,184,000us-gaap_TreasuryStockValue
Two Thousand Five Share Repurchase Program |  |
Equity, Class of Treasury Stock [Line Items] |  |
Shares repurchased program expiration date | Apr. 29, 2018 |
Two Thousand Five Share Repurchase Program | Class A |  |
Equity, Class of Treasury Stock [Line Items] |  |
Stock authorized to repurchase by board of directors | 800,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1 / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember / us-gaap_StatementScenarioAxis = mstr_TwoThousandFiveShareRepurchaseProgramMember |
Treasury stock, shares | 3,826,947us-gaap_TreasuryStockShares / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember / us-gaap_StatementScenarioAxis = mstr_TwoThousandFiveShareRepurchaseProgramMember |
Shares repurchased, average price per share | 90.23us-gaap_TreasuryStockAcquiredAverageCostPerShare / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember / us-gaap_StatementScenarioAxis = mstr_TwoThousandFiveShareRepurchaseProgramMember |
Treasury stock, cost | 345,300,000us-gaap_TreasuryStockValue / us-gaap_StatementClassOfStockAxis = us-gaap_CommonClassAMember / us-gaap_StatementScenarioAxis = mstr_TwoThousandFiveShareRepurchaseProgramMember |

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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- 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
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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
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- Definition Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28,29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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- 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://www.xbrl.org/2003/role/presentationRef -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 + Details
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