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Property, Plant and Equipment - Estimated Service Lives of Property, Plant and Equipment - Asset Used by The Company (Detail) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Land improvements [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P8Y
Land improvements [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P10Y | P10Y |
Land improvements [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P30Y
Land improvements [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P30Y | P30Y |
Main buildings [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P35Y
Main buildings [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P20Y | P20Y |
Main buildings [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P60Y
Main buildings [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P60Y | P60Y |
Other building facilities [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P3Y
Other building facilities [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P3Y | P3Y |
Other building facilities [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P20Y
Other building facilities [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P15Y | P15Y |
Computer equipment [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P2Y
Computer equipment [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P2Y | P2Y |
Computer equipment [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P8Y
Computer equipment [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P8Y | P8Y |
Telecommunication circuits [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P2Y
Telecommunication circuits [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P2Y | P2Y |
Telecommunication circuits [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P30Y
Telecommunication circuits [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P30Y | P30Y |
Telecommunication machinery and antennas equipment [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P2Y
Telecommunication machinery and antennas equipment [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P2Y | P2Y |
Telecommunication machinery and antennas equipment [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P30Y
Telecommunication machinery and antennas equipment [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P30Y | P30Y |
Transportation equipment [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P3Y
Transportation equipment [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P3Y | P3Y |
Transportation equipment [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P10Y
Transportation equipment [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P10Y | P10Y |
Leasehold improvements [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P1Y
Leasehold improvements [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P1Y | P1Y |
Leasehold improvements [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P6Y
Leasehold improvements [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P9Y | P9Y |
Mechanical and air conditioner equipment [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P3Y
Mechanical and air conditioner equipment [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P3Y | P3Y |
Mechanical and air conditioner equipment [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P16Y
Mechanical and air conditioner equipment [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P16Y | P16Y |
Others [Member] | Bottom of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P1Y
Others [Member] | Bottom of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P1Y | P1Y |
Others [Member] | Top of Range [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives |  |  | P10Y
Others [Member] | Top of Range [Member] | Assets Used by the Company [Member] |  |  |
Disclosure Of Property Plant And Equipment [Line Items] |  |  |
Estimated service lives | P15Y | P15Y |

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- Details
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- Details
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- Details
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- Details
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