Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Text Block] RECENT ACCOUNTING PRONOUNCEMENTS Goodwill and Intangible Assets Disclosure [Text Block] GOODWILL AND INTANGIBLE ASSETS Fair Value, Measurement Inputs, Disclosure [Text Block] FAIR VALUE MEASUREMENTS Debt Disclosure [Text Block] DEBT Noncontrolling Interest Disclosure [Text Block] NONCONTROLLING INTERESTS Stockholders' Equity Note Disclosure [Text Block] COMMON STOCK ISSUANCE Disclosure of Compensation Related Costs, Share-based Payments [Text Block] LONG-TERM INCENTIVE COMPENSATION Other Income and Other Expense Disclosure [Text Block] OTHER INCOME, NET Earnings Per Share [Text Block] EARNINGS PER SHARE Commitments and Contingencies Disclosure [Text Block] COMMITMENTS AND CONTINGENCIES Document and Entity Information CONSOLIDATED BALANCE SHEETS Assets [Abstract] ASSETS Assets, Current [Abstract] Current assets: Investment securities Marketable Securities and Derivative Instruments, Current Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale which are intended to be held for less than one year (4) derivative instruments which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer. Accounts Receivable, Net, Current Accounts receivable Income Taxes Receivable, Current Income taxes receivable Other Assets, Current Other current assets Assets, Current Total current assets Assets, Noncurrent [Abstract] Other assets: Other Assets, Noncurrent Other assets Property, Plant and Equipment, Net Property and equipment, net Intangible Assets, Net (Excluding Goodwill) Intangibles, net Goodwill Goodwill Assets. Total assets Liabilities and Stockholders' Equity [Abstract] LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities, Current [Abstract] Current liabilities: Accounts Payable, Current Accounts payable Employee-related Liabilities, Current Accrued compensation and benefits Long-term Debt, Current Maturities Current portion of long-term debt Liabilities, Current Total current liabilities Liabilities, Noncurrent [Abstract] Other liabilities: Deferred Tax Liabilities, Noncurrent Deferred income taxes Liabilities Total liabilities Commitments and Contingencies. Commitments and contingencies Redeemable noncontrolling interests Redeemable Noncontrolling Interests This represents the fair value of the redeemable noncontrolling interests that was effected through an increase to redeemable noncontrolling interests and a charge to retained earnings. Future changes in fair value will be recognized as increases or decreases to retained earnings. Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] STOCKHOLDERS' EQUITY Preferred Stock, Value, Issued Preferred stock ($1.00 par, 10,000,000 shares authorized, none issued) Retained Earnings (Accumulated Deficit) Retained earnings Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income Stockholders' Equity Attributable to Parent Total JCG stockholders' equity Stockholders' Equity Attributable to Noncontrolling Interest Noncontrolling interests Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total stockholders' equity Balance Balance Liabilities and Stockholders' Equity. Total liabilities and stockholders' equity CONSOLIDATED STATEMENTS OF INCOME Revenues [Abstract] Revenues: Investment Advisory Fees Investment management fees Performance Fees Performance fees Shareowner Servicing Fees and Other Revenue Shareowner servicing fees and other This element represents the shareholder servicing fees and other, includes transfer agent fees, distribution fees, service fees and money market administration fees. Revenues Total Labor and Related Expense Employee compensation and benefits Marketing and Advertising Expense Marketing and advertising Selling Expense Distribution General, administrative and occupancy General, Administrative and Occupancy The amount of general, administrative and occupancy expenses related to managing and administering the affairs of the entity. Operating Expenses Operating Income (Loss) Operating income (loss) Interest Expense Interest expense Gain (Loss) on Investments Investment gains (losses), net Investment (gains) losses, net Other Nonoperating Income (Expense) Other income, net Gains (Losses) on Extinguishment of Debt Gain on early extinguishment of debt Gain on early extinguishment of debt Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Cumulative Effects of Changes in Accounting Principles, Noncontrolling Interest Income (loss) before taxes and equity earnings Income Tax Expense (Benefit) Income tax provision Income (Loss) from Equity Method Investments Equity in earnings of unconsolidated affiliate Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest Income (loss) from continuing operations Net income (loss) Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Loss from discontinued operations Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net income (loss) Net income (loss) Net Income (Loss) Attributable to Noncontrolling Interest Noncontrolling interests Net Income (Loss) Attributable to Parent Net income (loss) attributable to JCG Net income (loss) Earnings Per Share, Basic [Abstract] Basic earnings (loss) per share attributable to JCG common shareholders: Income (Loss) from Continuing Operations, Per Basic Share Income (loss) from continuing operations (in dollars per share) Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share Loss from discontinued operations (in dollars per share) Earnings Per Share, Basic Basic (in dollars per share) Net income (loss) (in dollars per share) Earnings Per Share, Diluted [Abstract] Diluted earnings (loss) per share attributable to JCG common shareholders: Income (Loss) from Continuing Operations, Per Diluted Share Income (loss) from continuing operations (in dollars per share) Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share Loss from discontinued operations (in dollars per share) Earnings Per Share, Diluted Diluted (in dollars per share) Net income (loss) (in dollars per share) Income (Loss) from Continuing Operations Attributable to Parent Income (loss) from continuing operations CONSOLIDATED STATEMENTS OF CASH FLOWS Cash and Cash Equivalents, Period Increase (Decrease) [Abstract] CASH FLOWS PROVIDED BY (USED FOR): Cash and Cash Equivalents, Continuing Operations Period Increase (Decrease) [Abstract] Continuing Operations Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to net income: Deferred Income Tax Expense (Benefit) Deferred income taxes Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities, Other Other, net Increase (Decrease) in Operating Capital [Abstract] Changes in working capital items: Increase (Decrease) in Accounts Receivable Accounts receivable Increase (Decrease) in Other Operating Assets Other current assets Increase (Decrease) in Accounts Payable and Accrued Liabilities Accounts payable and accrued compensation payable Increase (Decrease) in Other Operating Liabilities Other liabilities Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net operating Payments to Acquire Property, Plant, and Equipment Purchase of property and equipment Payments to Acquire Businesses, Net of Cash Acquired Acquisitions Net Cash Provided by (Used in) Investing Activities, Continuing Operations Net investing Proceeds from Issuance of Long-term Debt Proceeds from issuance of long-term debt Payments of Debt Issuance Costs Debt issuance costs Repayments of Long-term Debt Repayment of long-term debt Proceeds from Issuance of Common Stock Issuance of common stock Payments to Noncontrolling Interests Purchase of noncontrolling interests Proceeds from Stock Plans Proceeds from stock plans Excess Tax Benefit from Share-based Compensation, Financing Activities Excess tax benefit from equity-based compensation Payments for Repurchase of Common Stock Repurchase of common stock Payments of Dividends, Noncontrolling Interest Distributions to noncontrolling interests Repayments of Long-term Capital Lease Obligations Principal payments under capital lease obligations Payments of Dividends, Common Stock Dividends paid to shareholders Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net financing Net Cash Provided by (Used in) Discontinued Operations [Abstract] Discontinued Operations Cash Provided by (Used in) Operating Activities, Discontinued Operations Operating activities Cash Provided by (Used in) Investing Activities, Discontinued Operations Investing activities Cash and Cash Equivalents: Cash and Cash Equivalents, Discontinuing Operations [Abstract] Net Cash Provided by (Used in) Discontinued Operations Net decrease Supplemental Cash Flow Information [Abstract] Supplemental Cash Flow Information: Interest Paid, Net Cash paid for interest Income Taxes Paid, Net Cash paid for income taxes Stock Issued During Period, Shares, Period Increase (Decrease) Stockholders' Equity, Period Increase (Decrease) Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity Statement [Line Items] Statement CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY Statement [Table] Statement, Equity Components [Axis] Equity Component [Domain] Common Stock Retained Earnings Accumulated Other Comprehensive Income (Loss) Cumulative Effect of Initial Adoption of New Accounting Principle Cumulative-effect adjustment for the adoption of a new accounting principle Other Comprehensive Income, Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax Reclassification for net gains included in net income Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax Foreign currency translation adjustment Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive income Amortization of stock-based compensation This element represents the stock-based compensation cost which is based on the grant date fair value of awards expected to vest at the end of the stated service period, comprised of the total value of the awards less an estimate for forfeitures. The grant date fair value of stock options is determined using the Black-Scholes option pricing model and the grant date fair value of restricted stock is determined from a quoted market price. The Black-Scholes model requires significant management estimates including volatility and expected life. Adjustments to Retained Earnings Capital, Amortization of Share-based Compensation Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Issuance and forfeitures of restricted stock awards, net (in shares) Tax impact of stock-based compensation This element represents the tax benefit associated with any share-based compensation plan other than an employee stock ownership plan (ESOP). Adjustments to Retained Earnings Capital, Tax Effect from Share-based Compensation Stock Issued During Period, Value, Stock Options Exercised Stock option exercises Stock Repurchased During Period, Value Repurchase of common stock Noncontrolling interests in consolidated investment products Noncontrolling interests that are not subject to put rights consist of third party investors in consolidated investment products, certain third party interests granted to employees, and undistributed earnings attributable to such interests. Certain of the third party interests granted to employees will become subject to put rights upon vesting. Minority Interest in Consolidated Investment Products Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests Purchase of noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Distributions to noncontrolling interests Noncontrolling Interest, Change in Redemption Value Change in value of redeemable noncontrolling interests Stock Issued During Period, Value, New Issues Common stock issuance Convertible debt issuance The amount of convertible debt issued during the period. The convertible debts are convertible under certain circumstances into cash. Issuance of Convertible Debt Common Stock, Dividends, Per Share, Declared Common stock dividends, per share (in dollars per share) Shares, Issued Balance (in shares) Balance (in shares) Stock Issued During Period, Shares, Stock Options Exercised Stock option exercises ( in shares) Stock Repurchased During Period, Shares Repurchase of common stock (in shares) Stock Issued During Period, Shares, New Issues Common stock issuance (in shares) Statement, Scenario [Axis] Scenario, Unspecified [Domain] Previously Reported Adjustment INVESTMENT SECURITIES This item represents the entire disclosure related to Marketable Securities and derivatives which may consist of all investments in certain debt and equity securities (and other assets). Marketable Securities and Derivatives [Text Block] Payments to Acquire Marketable Securities and Derivatives The cash outflow from purchases of trading, available-for-sale securities and held-to-maturity securities and derivatives. Purchase of investment securities The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities and derivatives (trading, held-to-maturity, or available-for-sale) during the period. Proceeds from Sale and Maturity of Marketable Securities and Derivatives Proceeds from sales and maturities of investment securities Common Stock, Value, Issued Common stock ($.01 par, 1,000,000,000 shares authorized; 265,500,708 and 265,500,708 shares issued, respectively; 184,100,855 and 182,024,431 shares outstanding, respectively) Other Comprehensive Income, Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Net unrealized gain (loss) on available-for-sale securities Distributions of Cash from Discontinued Operations Distribution of cash from discontinued operations The cash inflow resulting from the distribution of cash from the discontinued operations. Other Accrued Liabilities Current And Capital Lease Obligations, Current Other accrued liabilities Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Also includes amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date. Long-term Debt, Excluding Current Maturities Long-term debt Other Liabilities Noncurrent And Capital Lease Obligations, Noncurrent Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet due to materiality considerations. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer). Also includes amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date. Other liabilities Depreciation, Depletion and Amortization Depreciation and amortization Amortization of Deferred Sales Commissions Payment of deferred commissions, net Other Comprehensive Income, Derivatives Qualifying as Hedges, Net of Tax Amortization of net loss on cash flow hedge Dividends, Common Stock, Cash Common stock dividends ($0.04 per share) Summary of Income Tax Contingencies [Text Block] INCOME TAXES Comprehensive Income The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent, excluding the effect of redeemable noncontrolling interests. Net Income Loss Excluding Redeemable Noncontrolling Interests Net income (loss) attributable to JCG Costs and Expenses [Abstract] Operating expenses: Costs and Expenses Total Asset Impairment Charges Goodwill and intangible asset impairments Earnings Per Share [Abstract] Earnings (loss) per share attributable to JCG common shareholders: Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents At beginning of period At end of period Net Cash Provided by (Used in) Operating Activities [Abstract] Operating Activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Investing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Financing Activities: Net Cash Provided by (Used in) Operating Activities Net operating Net Cash Provided by (Used in) Investing Activities Net investing Net Cash Provided by (Used in) Financing Activities Net financing Cash and Cash Equivalents, Period Increase (Decrease) Net increase (decrease) Cash and Cash Equivalents, at Carrying Value [Abstract] Cash and Cash Equivalents: Other Comprehensive Income, Reclassification Adjustment for Write-down of Securities Included in Net Income, Net of Tax Impairment of available-for-sale securities Issuance and forfeitures of restricted stock awards Stock Issued During Period, Value, Employee Stock Purchase Plan Employee stock purchases Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Operating Activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Investing Activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Financing Activities: Cash and Cash Equivalents, Continuing Operations [Abstract] Cash and Cash Equivalents: Allocated Share-based Compensation Expense Long-term incentive compensation Amortization of Financing Costs and Discounts Amortization of debt discounts and deferred issuance costs Stock option exercises and employee stock purchases Stock Option Exercises And Employee Stock Purchases Value stock issued during the period as a result of the exercise of stock options and as a result of stock issued during the period for an employee stock purchase plan. Stock option exercises and employee stock purchases (in shares) Stock Option Exercises And Employee Stock Purchases, Shares Number of shares issued during the period as a result of the exercise of stock options and purchases through an employee stock purchase plan. Share-based Compensation Amortization of stock-based compensation Dividends Dividends paid to shareholders DESCRIPTION OF THE BUSINESS INVESTMENT SECURITIES FAIR VALUE MEASUREMENTS DEBT INCOME TAXES NONCONTROLLING INTERESTS LONG-TERM INCENTIVE COMPENSATION OTHER INCOME, NET EARNINGS PER SHARE COMMITMENTS AND CONTINGENCIES RECENT ACCOUNTING PRONOUNCEMENTS ACQUISITIONS GOODWILL AND INTANGIBLE ASSETS COMMON STOCK ISSUANCE General, Administrative and Occupancy Expenses General, Administrative and Occupancy Expenses General, Administrative and Occupancy Expenses [Text Block] Disclosure of general, administrative and occupancy expenses. Preferred stock, par (in dollars per share) 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 (in dollars per share) 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 Proceeds from (Payments for) Other Financing Activities Other, net SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES OTHER BALANCE SHEET CAPTIONS EMPLOYEE BENEFIT PLANS LITIGATION AND OTHER REGULATORY MATTERS RELATED PARTY TRANSACTIONS SHAREHOLDER RIGHTS PLAN SEGMENT AND GEOGRAPHIC INFORMATION QUARTERLY FINANCIAL DATA (UNAUDITED) Significant Accounting Policies [Text Block] RELATED PARTY TRANSACTIONS Related Party Transactions Disclosure [Text Block] SHAREHOLDER RIGHTS PLAN Shareholder Rights Plan Disclosure [Text Block] This element represents the disclosure of shareholders' rights plan of the reporting entity. Legal Matters and Contingencies [Text Block] LITIGATION AND OTHER REGULATORY MATTERS This is an aggregation element for disclosure of legal proceedings, legal contingencies, litigation, regulatory and environmental matters and other contingencies. These concepts can be reported in the notes to financial statements using a single element and can contain in one note the entire disclosure for these concepts. SEGMENT AND GEOGRAPHIC INFORMATION Segment Reporting Disclosure [Text Block] QUARTERLY FINANCIAL DATA (UNAUDITED) Quarterly Financial Information [Text Block] Net Income (Loss) Attributable to Parent [Abstract] Amounts attributable to JCG common shareholders: Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents At beginning of period At end of period DESCRIPTION OF THE BUSINESS Nature of Operations [Text Block] ACQUISITIONS Business Acquisitions and Dispositions, Disclosure [Text Block] Disclosure of all information related to any significant business acquisition and disposition completed during the period. Disclosure may include methodology and assumptions, including background, timing, and recognized assets and liabilities. This element may be used as a single block of text to encapsulate the entire disclosure (including data and tables). INCOME TAXES Income Tax Disclosure [Text Block] OTHER BALANCE SHEET CAPTIONS Supplemental Balance Sheet Disclosures [Text Block] This element encompasses the aggregate supplemental disclosures, including descriptions and amounts, related to assets, liabilities, and equity. This element may be used for the entire disclosure as a single block of text. EMPLOYEE BENEFIT PLANS Compensation and Employee Benefit Plans [Text Block] This element describes in a single footnote disclosure an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans. Cash and Cash Equivalents, Continuing Operations, at Carrying Value Cash and cash equivalents At beginning of period At end of period This element represents the Cash equivalents for continuing operations, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment including investments in money market funds, are considered cash equivalents continuing operations. Net Cash Provided by (Used in) Continuing Operations Net increase (decrease) The net change in cash associated with the entity's continuing operations. Basis of Presentation, Significant Accounting Policies and Account Detail [Text Block] SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES This element describes the basis of presentation and significant accounting policies. Disclosures also include other financial statement account detail. Noncontrolling Interest, Decrease from Vesting of Noncontrolling Interest Vesting of Perkins LLC interests Decrease in noncontrolling interest as a result of the vesting interest of a majority owned subsidiary. Nonredeemable Noncontrolling Interests in Subsidiary