Document and Entity Information [Abstract] Document and entity information. Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Document Fiscal Year Focus Document Fiscal Period Focus Current Fiscal Year End Date Entity Filer Category Entity Common Stock, Shares Outstanding Consolidated Statements of Operations [Abstract] Revenues: Revenues [Abstract] Rentals and Leases Rentals and leases The total amount of revenue recognized for the period from rentals and operating leases. Other Revenue, Net Sales of equipment and other revenues Revenues, Total Total revenues Operating expenses: Costs and Expenses [Abstract] Depreciation of rental and lease equipment Cost of Services, Depreciation Costs of sales of equipment and other revenues Cost of Goods Sold Selling, General and Administrative Expense Selling, general and administrative expenses Costs and Expenses, Total Total operating expenses Operating Income (Loss) Operating profit Business Combination, Bargain Purchase, Gain Recognized, Amount Gain on bargain purchase, net of taxes Gain on bargain purchase, net of deferred taxes Bargain purchase gain related to EMT Investment Income, Interest Interest income, net Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Income before income taxes Income Tax Expense (Benefit) Income tax provision Net Income (Loss) Attributable to Parent Net income Net income Computation of Earnings Per Share [Abstract] Earnings Per Share, Basic Basic Basic Earnings Per Share, Diluted Diluted Diluted Shares used in per share calculation: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted Average Number of Shares Outstanding, Basic Denominator for basic earnings per share - weighted average common shares outstanding Basic Weighted Average Number of Shares Outstanding, Diluted Diluted shares used in per share calculation Diluted Consolidated Balance Sheets [Abstract] Assets Assets [Abstract] Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Cash and cash equivalents at beginning of period Cash and cash equivalents Accounts receivable, net of allowance for doubtful accounts of $466 and $522 Accounts Receivable, Net Other property, net of accumulated depreciation and amortization of $18,398 and $17,832 Property, Plant and Equipment, Net Goodwill Goodwill, Ending Balance Goodwill, Beginning Balance Goodwill Intangibles, net of amortization of $1,386 and $1,304 Intangible Assets, Net (Excluding Goodwill) Net Carrying Amount Other Assets Total other assets Other assets Assets Total assets Liabilities and Shareholders' Equity Liabilities and Equity [Abstract] Liabilities: Liabilities [Abstract] Accounts Payable Accounts payable Accrued Liabilities Accrued expenses Deferred revenue Deferred Revenue Deferred Income Tax Liabilities Deferred tax liability Liabilities, Total Total liabilities Commitments and Contingencies Commitments and contingencies (Note 13) Shareholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $1 par - shares authorized 1,000,000; none issued Preferred Stock, Value, Issued Common stock, no par - shares authorized 40,000,000; issued and outstanding November 30, 2012 - 23,995,626; May 31, 2012 - 23,987,826 Common Stock, Value, Issued Retained Earnings (Accumulated Deficit) Retained earnings Stockholders' Equity Attributable to Parent, Total Total shareholders' equity Liabilities and Equity Total liabilities and shareholders' equity Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable Accumulated Depreciation Depletion and Amortization Property Plant and Equipment Rental and Lease Equipment Accumulated depreciation on rental and lease equipment Accumulated depreciation on rental and lease equipment Accumulated Depreciation Depletion and Amortization Other Property Accumulated depreciation and amortization for other property Accumulated depreciation and amortization for other property Finite-Lived Intangible Assets, Accumulated Amortization Accumulated Amortization Amortization of intangibles Preferred stock, par value Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Common stock, par value Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Common stock, shares outstanding Common Stock, Shares, Outstanding Statement [Line Items] Consolidated Statements of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Remeasurement Gain Loss Remeasurement loss on foreign currency Remeasurement loss on foreign currency Provision for losses on accounts receivable Provision for Doubtful Accounts Gain Loss on Sale of Rental and Lease Equipment Gain on sale of rental and lease equipment The gains and losses included in results of operations resulting from the sale or disposal or rental and lease equipment which do not qualify for treatment of discontinued operations. Stock compensation expense Share-based Compensation Excess Tax Benefit from Share-based Compensation, Operating Activities Excess tax benefit for share based compensation Deferred income taxes Deferred Income Tax Expense (Benefit) Change in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Increase (Decrease) in Accounts Receivable Accounts receivable Increase (Decrease) in Other Operating Assets Other assets Accounts payable Increase (Decrease) in Accounts Payable Accrued expenses Increase (Decrease) in Accrued Liabilities Increase (Decrease) in Deferred Revenue Deferred revenue Net Cash Provided by (Used in) Operating Activities Net cash provided by operating activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Proceeds from sale of rental and lease equipment Proceeds from Sale of Productive Assets Payments to Acquire Businesses, Net of Cash Acquired Cash paid for acquisition Payments to Acquire Productive Assets Payments for purchase of rental and lease equipment Payments to Acquire Property, Plant, and Equipment Payments for purchase of other property Net Cash Provided by (Used in) Investing Activities Net cash used in investing activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Payments Related to Tax Withholding for Share-based Compensation Minimum tax withholdings on share based compensation Excess tax benefit for share based compensation Excess Tax Benefit from Share-based Compensation, Financing Activities Payments of Dividends, Common Stock Payment of dividends Net Cash Provided by (Used in) Financing Activities Net cash used in financing activities Cash and Cash Equivalents, Period Increase (Decrease) Net increase (decrease) in cash and cash equivalents Effect of exchange rate changes on cash Effect of Exchange Rate on Cash and Cash Equivalents Basis of Presentation [Abstract] Fair Value Measurements [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Acquisitions [Abstract] Business Combination Disclosure [Text Block] Acquisitions Goodwill and Intangibles [Abstract] Goodwill and Intangibles Goodwill and Intangibles Disclosure [Text Block] Borrowings [Abstract] Borrowings Debt Disclosure [Text Block] Income Taxes [Abstract] Income Taxes Income Tax Disclosure [Text Block] Sales Type Leases [Abstract] Computation of Earnings Per Share Earnings Per Share [Text Block] Commitments and Contingencies [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Equity Incentive Plan [Abstract] Equity Incentive Plan Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Segment Reporting and Related Disclosures [Abstract] Segment Reporting and Related Disclosures Segment Reporting Disclosure [Text Block] Cash and Cash Equivalents Disclosure [Text Block] Cash and Cash Equivalents Cash and Cash Equivalents [Abstract] Supplemental Cash Flow Information [Abstract] New Accounting Pronouncements, Policy [Policy Text Block] Recent Accounting Pronouncements Minimum Lease Payments Receivable and Net Investment [Table Text Block] Minimum lease payments receivable and the net investment Tabular disclosure for minimum lease payments receivable and the net investment. Revenues from Rental Lease and Sale Segment [Table Text Block] Tabular disclosure for revenues from rental, lease and sale segment. Revenues from rental, lease and sale segment Schedule of Other Assets [Table Text Block] Summary of other assets Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Estimated fair values of the assets acquired and liabilities assumed Schedule of Intangible Assets and Goodwill [Table Text Block] Changes in carrying amount of goodwill and other intangible assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Amortization of Intangible assets with finite useful lives Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Estimated future amortization expense related to intangible assets Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block] Estimated future minimum lease payments receivable related to sales-type leases Revenues from external customers and long-lived assets, by geographical areas Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block] Schedule of Calculation of Numerator and Denominator in Earnings Per Share [Table Text Block] Reconciliation of the denominator used in the computation of basic and diluted earnings per share Foreign Exchange Forward [Member] Foreign exchange forward contracts [Member] Accrued Liabilities [Member] Accrued expenses [Member] Other Assets [Member] Other assets [Member] Not Designated as Hedging Instrument [Member] Derivatives Not Designated as Hedging Instruments [Member] Selling General and Administrative Expense [Member] Selling, general and administrative expense [Member] Selling general and administrative expense. Derivative Instruments Gain Loss [Abstract] Gains and losses recognized in income for derivative instruments Derivative instruments gain loss. Other Assets [Abstract] Summary of other assets Capital Leases, Net Investment in Sales Type Leases Net investment in sales-type lease receivables Net investment in sales-type leases Demonstration Equipment Demonstration equipment Demonstration equipment Demonstration equipment. Supplemental Executive Retirement Plan Assets Supplemental executive retirement plan Supplemental executive retirement plan assets This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. Income Taxes Receivable Income taxes receivable Prepaid Expense and Other Assets Prepaid expenses and other Assets Liabilities Revenues and Expenses of Foreign Subsidiaries Assets, liabilities, revenues and expenses of foreign subsidiaries Assets, liabilities, revenues and expenses of foreign subsidiaries. Period for Demonstration Equipment Included in Other Assets Period for demonstration equipment included in other assets Period for demonstration equipment included in other assets. Basis of Presentation (Textual) [Abstract] Basis of Presentation (Textual) [Abstract] Basis of presentation. Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Derivative Instrument Risk [Axis] Derivative Contract Type [Domain] Hedging Designation [Axis] Hedging Designation [Domain] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Derivatives, Fair Value [Line Items] Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Income Statement Location [Axis] Income Statement Location [Domain] Derivative Instruments, Gain (Loss) [Line Items] Range [Axis] Range [Domain] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value, Inputs, Level 1 [Member] Quoted Prices in Active Markets for Identical Instruments (Level 1) [Member] Fair Value, Inputs, Level 2 [Member] Significant Other Observable Inputs (Level 2) [Member] Fair Value, Inputs, Level 3 [Member] Significant Unobservable Inputs (Level 3) [Member] Money Market Funds [Member] Money market funds [Member] Supplemental Employee Retirement Plans, Defined Benefit [Member] Supplemental executive retirement plan [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Business Acquisition, Purchase Price Allocation [Abstract] Estimated fair values of the assets acquired and liabilities assumed Business Acquisition, Purchase Price Allocation, Current Assets, Receivables Acquired gross accounts receivable Accounts receivable Deferred taxes, net Business Acquisition, Purchase Price Allocation, Deferred Tax Liabilities, Noncurrent Deferred tax liability Business Acquisition, Purchase Price Allocation, Current Liabilities, Deferred Revenue Deferred revenue Acquisition (Textual) [Abstract] Acquisition. Acquisition (Textual) [Abstract] Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Net assets acquired Business Combination, Acquisition Related Costs Acquisition-related transaction cost Business Acquisition Purchase Price Allocation Deferred Tax Net Deferred taxes, net Acquisition purchase price allocation deferred tax net. Nonvested, Restricted Stock Units, beginning balance Nonvested, Restricted Stock Units, ending balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted, Restricted Stock Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Restricted stock units granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Vested, Restricted Stock Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Forfeited/canceled, Restricted Stock Units Nonvested, Weighted Average Grant Date Fair Value, ending balance Nonvested, Weighted Average Grant Date Fair Value, beginning balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Vested, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited/canceled, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Restricted Stock Units (RSUs) [Member] Restricted Stock Units [Member] Equity Incentive Plan (Textual) [Abstract] Equity incentive plan. Equity Incentive Plan (Textual) [Abstract] Two Thousand Five Equity Incentive Plan [Member] 2005 Equity Incentive Plan [Member] 2005 equity incentive plan. Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Domain] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Plan Name [Axis] Plan Name [Domain] Stock Options [Member] Stock Options [Member] Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options Unrecognized share based compensation cost Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition Expected period to recognize the unrecognized share based compensation cost Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Maximum number of shares authorized Share-based Compensation Arrangement by Share-based Payment Award, Expiration Date Expiration date Allocated Share-based Compensation Expense, Net of Tax Allocated share based compensation Employee Service Share-based Compensation, Tax Benefit from Compensation Expense Total tax benefit realized Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options Cash received from stock option exercises Old Stock Options Plan [Member] Old stock options plan. Prior stock option plans [Member] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Outstanding options in prior stock option plans Customer relationships, Ending Balance Customer relationships, Beginning Balance Finite-Lived Intangible Assets, Net Customer relationships, Net Carrying Amount Total intangible assets Amortization of Intangible Assets Amortization Amortization expense of intangible assets Finite-Lived Intangible Asset, Useful Life Estimated Useful Life Finite-Lived Intangible Assets, Gross Gross Carrying Amount Trade Names [Member] Trade name [Member] Customer Relationships [Member] Customer relationships [Member] Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2013 (remaining) Finite-Lived Intangible Assets, Amortization Expense, Year Two 2014 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2015 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2016 Finite-Lived Intangible Assets, Amortization Expense, Year Five 2017 Finite-Lived Intangible Assets, Amortization Expense, after Year Five Thereafter Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Estimated future amortization expense related to intangible assets Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets [Line Items] EMT [Member] EMT. EMT [Member] Telogy [Member] Telogy. Telogy [Member] Rush Computer Rentals, Inc. [Member] Rush Computer Rentals, Inc. Rush Computer Rentals, Inc. [Member] Goodwill and Intangibles (Textual) [Abstract] Goodwill and Intangibles (Textual) [Abstract] Goodwill and intangibles. Business Acquisition, Effective Date of Acquisition Date of Acquisition Borrowings (Textual) [Abstract] Borrowings. Borrowings (Textual) [Abstract] Line of Credit Facility, Maximum Borrowing Capacity Maximum aggregate outstanding principal amount under Commercial Credit Agreement Line of Credit Facility, Expiration Date Maturity date of Commercial Credit Agreement Line of Credit Facility [Table] Credit Facility [Axis] Credit Facility [Domain] Line of Credit Facility [Line Items] Maximum [Member] Maximum [Member] Minimum [Member] Minimum [Member] Rental and Lease Equipment [Member] Rental and lease equipment [Member] Rental and lease equipment. Demonstration Equipment [Member] Demonstration equipment. Demonstration Equipment [Member] Noncash or Part Noncash Acquisitions [Table] Noncash or Part Noncash Acquisitions by Unique Description [Axis] Noncash or Part Noncash Acquisition, Name [Domain] Noncash or Part Noncash Acquisitions [Line Items] Minimum lease payments receivable and the net investment Capital Leases, Net Investment in Sales Type Leases [Abstract] Capital Leases, Net Investment in Sales Type Leases, Minimum Payments to be Received Gross minimum lease payments receivable Capital Leases, Future Minimum Payments Receivable, Fiscal Year Maturity [Abstract] Estimated future minimum lease payments receivable related to sales-type leases Capital Leases, Future Minimum Payments, Receivable in Two Years 2014 Capital Leases, Future Minimum Payments, Receivable in Three Years 2015 Capital Leases, Future Minimum Payments, Receivable in Four Years 2016 Capital Leases, Future Minimum Payments, Receivable in Five Years 2017 Capital Leases, Future Minimum Payments Receivable Total Revenues from Rental Lease and Sale Segment [Abstract] Revenues from rental, lease and sale segment Revenues from rental, lease and sale segment. Test and Measurement Equipment [Member] T&M [Member] Test and measurement (T&M) equipment. Data Products Equipment [Member] DP [Member] Data products ("DP") equipment. Revenues from External Customers and Long Lived Assets by Geographical Areas [Abstract] Revenues from external customers and long-lived assets, by geographical areas Revenues from external customers and long-lived assets, by geographical areas. Revenue, Net [Abstract] Revenues: Net Long Lived Assets [Abstract] Net Long-Lived Assets: Net long-lived assets. Long-Lived Assets Total net long-lived assets Segment Reporting and Related Disclosures (Textual) [Abstract] Segment Reporting and Related Disclosures (Textual) [Abstract] Segment reporting and related disclosures. Segment Reporting and Related Disclosures (Additional Textual) [Abstract] Segment Reporting and Related Disclosures (Additional Textual) [Abstract] Segment reporting and related disclosures. Number of Operating Segments Number of Operating segment Number of Customer for Reportable Segment Number of major customer accounted Number of customer for reportable segment. Revenue from External Customers by Products and Services [Table] Products and Services [Axis] Products and Services [Domain] Revenue from External Customer [Line Items] Denominator [Abstract] Denominator: Denominator. Dilutive effect of restricted stock Weighted Average Number Diluted Shares Outstanding Adjustment Income Tax Examination, Penalties and Interest Accrued Interest and penalties Right of Restricted Stock Units on shares Right of restricted stock unit to receive common stock Right of restricted stock units on shares. Asset Class [Axis] Fair Value by Asset Class [Domain] Basis of Presentation and Significant Accounting Policies [Text Block] Basis of Presentation Schedule of Derivative Instruments Not Designated as Hedging Instrument Gain Loss in Statement of Financial Performance [Table Text Block] Gains and losses recognized in income for derivative instruments Schedule of derivative instruments not designated as hedging instrument gain loss in statement of financial performance. Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Assets and liabilities measured at fair value on a recurring basis Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments Gains and losses recognized in income for derivative instruments Schedule of Property, Plant and Equipment [Table] Selling, General and Administrative Expenses [Member] Selling, General and Administrative Expenses [Member] Escrow Deposit Deposited into an escrow account for any post-closing adjustments Business Combination, Acquired Receivables, Estimated Uncollectible Acquired gross accounts receivable not expected to be collected Business Combination, Acquired Receivables, Fair Value Acquired gross accounts receivable resulting in fair value Increase Decrease in Business Combination Separately Recognized Transactions Revenues and Gains Recognized Increased bargain purchase gain Increase decrease in business combination separately recognized transactions revenues and gains recognized. Escrow Deposit Disbursements Related to Property Acquisition Post closing adjustments, disbursed from the escrow funds Share Based Compensation Arrangement by Share Based Payment Award Disclosure [Abstract] Summary of restricted stock unit activity Share based compensation arrangement by share based payment award disclosure. Commercial Credit Agreement [Member] Commercial credit agreement. Commercial Credit Agreement [Member] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Revenue from Rentals and Leases Service Rentals and leases Revenue from rentals and leases service. Revenue from Sales of Equipment and other Revenues Sales of equipment and other revenues Revenue from sales of equipment and other revenues. Tax Impact Realization Likelihood Percentage Tax impact realization likelihood percentage Tax impact realization likelihood percentage. Deferred Tax Assets, Unrealized Currency Losses Deferred tax assets unrealized currency losses Income Taxes (Textual) [Abstract] Income Taxes (Textual) [Abstract] Income taxes. Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring [Member] Business Acquisition, Cost of Acquired Entity, Cash Paid Total cash consideration Business Acquisition Purchase Price Allocations Deferred Tax Liabilities Noncurrent Bargain purchase gain, net of deferred taxes of $2,092 Business acquisition purchase price allocations deferred tax liabilities noncurrent. Assets, Fair Value Disclosure [Abstract] Assets and liabilities measured at fair value on a recurring basis Preliminary Purchase Price Allocation [Abstract] Preliminary purchase price allocation. Preliminary purchase price allocation Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Reconciliation of the denominator used in the computation of basic and diluted earnings per share Amortization of Intangible assets with finite useful lives Intangible Assets, Net (Excluding Goodwill) [Abstract] Electronic Test Equipment Rental and lease equipment, net of accumulated depreciation of $215,366 and $204,108 Rental and lease equipment Electronic test equipment. Capital Leases in Financial Statements of Lessor Disclosure [Text Block] Sales-Type Leases Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Fair value of foreign exchange forward contracts Summary of restricted stock unit activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net [Abstract] Fair value of foreign exchange forward contracts Foreign exchange forward contracts Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value Foreign exchange forward contracts other assets Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value Foreign exchange forward contracts Foreign exchange forward contracts accrued expenses Cash and Cash Equivalents, Fair Value Disclosure Money market funds Revenues from acquired assets Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual Income before income taxes from acquired assets Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual Less - unearned interest Capital Leases, Net Investment in Sales Type Leases, Deferred Income Capital Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year 2013 (remaining) Rental and Lease Equipment Equipment pool, based on acquisition cost Rental and lease equipment Other Disclosure on Geographic Areas, Revenue from External Customers Attributed to Foreign Countries U.S. Disclosure on Geographic Areas, Revenue from External Customers Attributed to Entity's Country of Domicile Disclosure on Geographic Areas, Long-Lived Assets in Entity's Country of Domicile U.S. Other Disclosure on Geographic Areas, Long-Lived Assets in Foreign Countries Indefinite-Lived Trade Names Trade names, Gross Carrying Amount Customer Relationships, Gross Carrying Amount Finite-Lived Customer Relationships, Gross Changes in Carrying Amount of Goodwill and Other Intangible Assets [Abstract] Changes in carrying amount of goodwill and other intangible assets Changes in carrying amount of goodwill and other Intangible assets. Intangible Assets, Net (Including Goodwill) Goodwill and other intangible assets, Ending balance Goodwill and other intangible assets, Beginning balance Goodwill and other intangible assets Intangible Assets Additions Including Goodwill Goodwill and other intangible assets, Additions Intangible assets additions including goodwill. Goodwill, Acquired During Period Goodwill, Additions Trade name, Additions Indefinite-lived Intangible Assets, Acquired During Period Supplemental Executive Retirement Plan Liabilities Supplemental executive retirement plan Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity. Common Stock, Dividends, Per Share, Cash Paid Cash dividend paid per common share Cash Flow, Supplemental Disclosures [Text Block] Supplemental Cash Flow Information Supplemental Cash Flow Information (Textual) [Abstract] Supplemental Cash Flow Information (Textual) [Abstract] Supplemental cash flow information. Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Supplemental Disclosures of Cash Paid (Refunded) Interest Paid Interest Income Taxes Paid Income taxes Minimum Percentage of Revenue Accounted for Major Customer Minimum percentage of revenue accounted for major customer Minimum percentage of revenue accounted for major customer. Earnings Per Share, Basic and Diluted [Abstract] Earnings per share: Business Acquisition, Purchase Price Allocation, Intangible Assets Other than Goodwill Estimated fair value of customer relationships acquired Business Acquisition, Purchase Price Allocation, Other Assets Determination of assets acquired and other components Minimum Percentage for Fair Market Value of Grant Minimum percentage for fair market value of grant Minimum percentage for fair market value of grant. Trade name, Ending balance Trade name, Beginning balance Indefinite-Lived Intangible Assets (Excluding Goodwill) Customer relationships, Additions Finite-lived Intangible Assets Acquired Indefinite-lived Intangible Assets by Major Class [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Supplemental Disclosures of Cash Paid Refunded [Abstract] Supplemental Disclosures of Cash Paid (Refunded) Supplemental disclosures of cash paid (refunded). Assets, Fair Value Disclosure, Recurring Total assets measured at fair value Liabilities, Fair Value Disclosure, Recurring Total liabilities measured at fair value Transfer of Demonstration Equipment to Inventory Transferred demonstration equipment to rental and lease equipment during the period Transfer of demonstration equipment to inventory. Capital Expenditures Incurred but Not yet Paid Accounts payable related to acquired rental and lease equipment Costs of Rental and Lease Equipment Excluding Depreciation Costs of rental and lease, excluding depreciation Costs of rental and lease equipment, excluding depreciation. Basis of Presentation (Additional Textual) [Abstract] Basis of Presentation (Additional Textual) [Abstract] Comprehensive Income, Policy [Policy Text Block] Other Comprehensive Income Foreign Currency Transactions and Translations Policy [Policy Text Block] Foreign Currency Proceeds from Long-term Lines of Credit Borrowing under bank line of credit Repayments of Long-term Lines of Credit Payment under bank line of credit Subsequent Events [Text Block] Subsequent Events Revenue Recognition, Policy [Policy Text Block] Revenue Recognition Subsequent Events [Abstract] Shipping, Handling and Transportation Costs Shipping and handling cost Dividends Payable Accrued dividends Accrued Dividend Supplemental Cash Flow Information (Additional Textual) [Abstract] Supplemental Cash Flow Information (Additional Textual) [Abstract] Subsequent Events (Textual) [Abstract] Subsequent Events (Textual) [Abstract] Common Stock, Dividends, Per Share, Declared Quarterly cash dividend per common share Dividends Payable, Date Declared Dividend declared date Dividends Payable, Date to be Paid Dividend payable date Operating Expenses [Policy Text Block] Operating expenses. Operating expenses Other Assets [Policy Text Block] Other assets. Other Assets Reclassification, Policy [Policy Text Block] Reclassifications Operating Leases Lease Term Operating lease agreements Period Operating leases lease term. Capital Lease Term Finance lease agreements Period Capital lease term. Reduction in Selling, General and Administrative Expenses Reduction in selling, general and administrative expenses. Reduction in selling, general and administrative expenses Line of Credit Facility, Commitment Fee Amount Commitment Fees Line of Credit Facility, Decrease, Repayments Borrowed and Repaid Line of Credit Facility, Increase, Additional Borrowings Borrowed Common Stock Special Dividends Per Share Declared Special dividend per common share Common stock special dividends per share declared. Dividend Funded from Cash on Hand Dividend funded from cash on hand Dividend funded from cash on hand. Dividend Funded by Borrowing Dividend funded by borrowing Dividend funded by borrowing. Schedule of Intangible Assets [Table] Schedule of intangible assets. Schedule of Intangible Assets [Line Items]