Income tax and deferred taxes (Details 10) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of accounting profit multiplied by applicable tax rates [abstract]
Consolidated income before taxes	$ 238,538	$ 390,622	$ 621,038
Income tax rate in force in Chile	27.00%	27.00%	27.00%
Tax expense using the statutory tax rate	$ (64,405)	$ (105,468)	$ (167,680)
Net effect of royalty tax payments	(4,659)	(4,314)	(4,919)
Effect of fines affected by article 21 and passive income	(1,804)	(724)	(2,957)
Tax effect of revenue from regular activities exempt from taxation	1,786	2,376	1,446
Tax rate effect of non-tax-deductible expenses for determining taxable profit (loss)	(2,987)	(2,128)	(2,327)
Tax effect of tax rates supported abroad	(2,077)	(252)	(8,714)
Surplus provision Internal revenue service	0	0	3,517
Effects of changes resulting from classifying a permanent item as a temporary one	4,826	0	0
Other tax effects from the reconciliation between the accounting income and tax expense	(859)	491	2,659
Tax expense using the effective rate	$ (70,179)	$ (110,019)	$ (178,975)

The amount of profit (loss) for a period before deducting tax expense. [Refer: Profit (loss)]

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The applicable income tax rate.

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that the entity does not separately disclose in the same statement or note. [Refer: Accounting profit; Applicable tax rate]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to expenses not deductible in determining taxable profit (tax loss). [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to foreign tax rates. [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to revenues that are exempt from taxation. [Refer: Accounting profit]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to tax losses. [Refer: Accounting profit]

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The product of the accounting profit multiplied by the applicable tax rate(s). [Refer: Accounting profit; Applicable tax rate]

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Effective of changes resulting from classifying a permanent item as a temporary one.

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Effective of fines imposed by article twenty one and tax income.

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to IRS provision surplus.

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