XML 106 R90.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Contents of Significant Accounts - Reconciliation Between Income Tax Expense and Income Before Tax At UMC's Applicable Tax Rate (Detail)
$ in Thousands, $ in Thousands
 12 Months Ended
Dec. 31, 2023
TWD ($)
Dec. 31, 2023
USD ($)
Dec. 31, 2022
TWD ($)
Dec. 31, 2021
TWD ($)
Reconciliation of accounting profit multiplied by applicable tax rates [abstract]        
Income before tax $ 68,450,404 $ 2,235,480 $ 109,625,660 $ 58,496,432
At UMC's statutory income tax rate 13,690,081   21,925,132 11,699,286
Adjustments in respect of current income tax of prior periods (217,891)   (585,941) (150,260)
Net changes in loss carry-forward and investment tax credits (2,179,234)   (465,152) (845,267)
Adjustment of deferred tax assets/liabilities for write-downs/reversals and different jurisdictional tax rates 211,639   (281,319) 183,123
Tax effect of non-taxable income and non-deductible expenses:        
Tax exempt income (1,428,035)   (4,384,566) (3,258,695)
Investment loss (gain) (755,800)   1,827,822 (1,388,877)
Dividend income (323,182)   (423,027) (171,725)
Others (145,520)   (340,745) 6,463
Basic tax 43,506   0 0
Estimated income tax on unappropriated earnings (1,160,324)   1,247,910 1,558,031
Effect of different tax rates applicable to UMC and its subsidiaries 234,510   605,929 116,174
Taxes withheld in other jurisdictions 38,346   35,979 43,443
Others 303,174   164,873 126,556
Income tax expense recorded in profit or loss $ 8,311,270 $ 271,433 $ 19,326,895 $ 7,918,252