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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax Expense Benefit [Line Items] |  |  |
Interest expense, domestic deposits | $ 40.1 | $ 65.8 | $ 64.2
Net unrecognized tax benefits | 9.4 | 8.8 |
Accrued interest and penalties related to unrecognized tax benefits | $ 3.1 | 2.9 |
Open tax year | 2011 2012 |  |
Deferred tax liabilities | $ 490.8 | 445.3 |
Undistributed earnings of foreign subsidiaries | $ 574.0 | $ 631.0 |
Federal statutory rate | 21.00% | 21.00% | 35.00%
Deferred income taxes | $ 945.6 | $ 806.2 |
Noncurrent Liabilities [Member] |  |  |
Income Tax Expense Benefit [Line Items] |  |  |
Deferred tax liabilities | 127.5 | 106.9 |
Deferred minimum tax credits | 14.3 |  |
General Business Tax Credits [Member] |  |  |
Income Tax Expense Benefit [Line Items] |  |  |
Deferred tax credits | $ 937.2 |  |
Deferred tax credits expiration year | 2034 |  |
State Tax Credits [Member] |  |  |
Income Tax Expense Benefit [Line Items] |  |  |
Deferred tax credits | $ 10.6 |  |
Deferred tax credits expiration year | 2023 |  |
HR One [Member] |  |  |
Income Tax Expense Benefit [Line Items] |  |  |
Deferred income taxes |  | 2.9 | $ 1.0
U.S. repatriation tax rate |  |  | 10.00%
U.S. repatriation tax amount |  | $ 2.9 | $ 40.0

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