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Cover [Abstract] Purchased content Purchased Content [Member] Purchased content. Fair Value Measurement Inputs and Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Equity Awards Adjustments Equity Awards Adjustments [Member] Total liabilities and shareholders’ equity Liabilities and Equity Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Mortgage loans held for sale Increase (Decrease) in Loan, Mortgage, Held-for-Sale Option awards Share-Based Payment Arrangement, Option [Member] Segments [Axis] Segments [Axis] Bank of Nova Scotia Bank of Nova Scotia [Member] Bank of Nova Scotia Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Restructuring charges Restructuring Charges Weighted- Average Exercise Price Per Share Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Plan Name [Axis] Plan Name [Axis] Income Tax Authority [Domain] Income Tax Jurisdiction [Domain] Tabular List, Table Tabular List [Table Text Block] Vesting [Axis] Vesting [Axis] Other long-term liabilities Increase (Decrease) in Other Noncurrent Liabilities Purchases of intangible assets Payments to Acquire Intangible Assets Total assets measured at fair value on a recurring basis, Amortized cost Cash, Cash Equivalents, and Short-Term Investments, Amortized Cost Cash, Cash Equivalents, and Short-Term Investments, Amortized Cost Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Aggregate Intrinsic Value, Outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period General and administrative General and Administrative Expense Property, Plant and Equipment, Type [Domain] Long-Lived Asset, Class [Domain] Stock Issued During Period, Value, Conversion of Convertible Securities Stock Issued During Period, Value, Conversion of Convertible Securities Preferred stock, authorized (in shares) Preferred Stock, Shares Authorized Property, Plant, and Equipment [Table] Property, Plant, and Equipment [Table] Preferred stock, $0.0001 par value; 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