Personnel expenses (Details 1) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Classes of employee benefits expense [abstract]
Wages and salaries	R$ 5,713,702	R$ 5,377,284	R$ 4,655,400
Social security costs	1,381,229	1,273,486	1,316,282
Benefits	1,309,314	1,277,781	1,183,902
Defined benefit pension plans (note 24)	20,081	24,481	31,332
Contributions to defined contribution pension plans	87,099	86,576	78,785
Share-based compensation	87,293	86,963	175,976
Training	58,338	62,518	92,883
Other personnel expenses	280,222	188,176	264,232
Total	R$ 8,937,278	R$ 8,377,265	R$ 7,798,792

Social security costs

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- Definition

Training

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No definition available.

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- Definition

Adjustments for share-based payments to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss)]

+ References

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No definition available.

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- Definition

The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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The amount of employee expenses that the entity does not separately disclose in the same statement or note.

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The amount of expense from employee benefits (other than termination benefits), which are expected to be settled wholly within twelve months after the end of the annual reporting period in which the employees render the related services, that the entity does not separately disclose in the same statement or note. [Refer: Employee benefits expense]

+ References

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- Definition

The amount of post-employment benefit expense relating to defined benefit plans. [Refer: Defined benefit plans [member]]

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The amount of post-employment benefit expense relating to defined contribution plans. Defined contribution plans are post-employment benefit plans under which an entity pays fixed contributions into a separate entity (a fund) and will have no legal or constructive obligation to pay further contributions if the fund does not hold sufficient assets to pay all employee benefits relating to employee service in the current and prior periods.

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- Definition

A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense]

+ References

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