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v3.19.1

Cash and Cash Equivalents - Annual Yield Rates of Bank Deposits, Commercial Paper, Negotiable Certificates of Deposit and Time Deposits (Detail) | Dec. 31, 2018 | Dec. 31, 2017
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Bank deposits [Member] | Bottom of range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.00% | 0.00%
Bank deposits [Member] | Top of Range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.50% | 0.70%
Commercial paper [Member] | Bottom of range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.47% | 0.32%
Commercial paper [Member] | Top of Range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.57% | 0.40%
Negotiable certificate of deposit [Member] | Bottom of range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.55% | 0.40%
Negotiable certificate of deposit [Member] | Top of Range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.60% | 0.50%
Time deposits [Member] | Bottom of range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 0.09% | 0.52%
Time deposits [Member] | Top of Range [Member] |  |
Disclosure of cash and cash equivalents [Line Items] |  |
Yield rate | 4.40% | 4.40%

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- Details
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- Details
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- Details
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- Details
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