Segments - Total Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total assets	$ 169,051	$ 155,430
Total assets, excluding assets held for sale	148,982	135,385
Assets held for sale	20,069	20,045
Corporate
Segment Reporting Information [Line Items]
Total assets	25,206	25,185
Total Voya Financial, Inc. Shareholders' Equity | Total Segment
Segment Reporting Information [Line Items]
Total assets	147,092	133,430
Consolidation of investment entities
Segment Reporting Information [Line Items]
Total assets	1,890	1,955
Operating Segments | Retirement
Segment Reporting Information [Line Items]
Total assets	118,024	104,995
Operating Segments | Investment Management
Segment Reporting Information [Line Items]
Total assets	745	690
Operating Segments | Employee Benefits
Segment Reporting Information [Line Items]
Total assets	$ 3,117	$ 2,560