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v3.19.1

Future Impact of Recently Issued Accounting Standards Not Yet in Effect - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2018
Bottom of range [member] |
Disclosure of impact of new accounting standards [line items] |
Percentage of right-of-use assets | 8.50%
Top of range [member] |
Disclosure of impact of new accounting standards [line items] |
Percentage of right-of-use assets | 9.50%

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- Definition Line items represents impact of new accounting standards. + References No definition available. + Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Percentage of right-of-use assets. + References No definition available. + Details
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Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |