Schedule II - Condensed Financial Information of Parent - Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments:
Fixed maturities, available-for-sale, at fair value	$ 39,663.0	$ 36,897.0
Limited partnerships/corporations	1,290.0	982.0
Derivatives	316.0	194.0
Investments in subsidiaries	0.0	0.0
Total investments	53,687.0	50,615.0
Cash and cash equivalents	1,181.0	1,237.0	$ 854.0
Short-term investments under securities loan agreements, including collateral delivered	1,395.0	1,293.0
Loans to subsidiaries and affiliates	0.0	0.0
Due from subsidiaries and affiliates	0.0	0.0
Deferred income taxes	1,458.0	1,610.0
Other assets	902.0	1,027.0
Liabilities and Shareholders' Equity:
Short-term debt	1.0	1.0
Long-term debt	3,042.0	3,136.0
Derivatives	403.0	164.0
Due to subsidiaries and affiliates	0.0	0.0
Other liabilities	1,345.0	1,375.0
Shareholders' equity:
Preferred stock ($0.01 par value per share; $625 and $325 aggregate liquidation preference as of 2019 and 2018, respectively)	0.0	0.0
Common stock ($0.01 par value per share; 900,000,000 shares authorized; 140,726,677 and 272,431,745 shares issued as of 2019 and 2018, respectively; 132,325,790 and 150,978,184 shares outstanding as of 2019 and 2018, respectively)	2.0	3.0
Treasury stock (at cost; 8,400,887 and 121,453,561 shares as of 2019 and 2018, respectively)	(460.0)	(4,981.0)
Additional paid-in capital	11,184.0	24,316.0
Accumulated other comprehensive income (loss)	3,331.0	607.0	2,731.0
Retained earnings (deficit):
Unappropriated	(4,649.0)	(11,732.0)
Total Voya Financial, Inc. shareholders' equity	9,408.0	8,213.0
Parent Issuer
Investments:
Fixed maturities, available-for-sale, at fair value	5.0	0.0
Limited partnerships/corporations	4.0	0.0
Derivatives	49.0	39.0
Investments in subsidiaries	11,003.0	10,099.0
Total investments	11,061.0	10,237.0
Cash and cash equivalents	212.0	209.0	$ 244.0
Short-term investments under securities loan agreements, including collateral delivered	11.0	11.0
Loans to subsidiaries and affiliates	164.0	79.0
Due from subsidiaries and affiliates	2.0	2.0
Deferred income taxes	816.0	553.0
Other assets	7.0	13.0
Total assets	12,273.0	11,104.0
Liabilities and Shareholders' Equity:
Short-term debt	69.0	4.0
Long-term debt	2,669.0	2,763.0
Derivatives	50.0	39.0
Due to subsidiaries and affiliates	4.0	1.0
Current income taxes	28.0	37.0
Other liabilities	45.0	47.0
Total liabilities	2,865.0	2,891.0
Shareholders' equity:
Preferred stock ($0.01 par value per share; $625 and $325 aggregate liquidation preference as of 2019 and 2018, respectively)	0.0	0.0
Common stock ($0.01 par value per share; 900,000,000 shares authorized; 140,726,677 and 272,431,745 shares issued as of 2019 and 2018, respectively; 132,325,790 and 150,978,184 shares outstanding as of 2019 and 2018, respectively)	2.0	3.0
Treasury stock (at cost; 8,400,887 and 121,453,561 shares as of 2019 and 2018, respectively)	(460.0)	4,981.0
Additional paid-in capital	11,184.0	24,316.0
Accumulated other comprehensive income (loss)	3,331.0	607.0
Retained earnings (deficit):
Unappropriated	(4,649.0)	(11,732.0)
Total Voya Financial, Inc. shareholders' equity	9,408.0	8,213.0
Total liabilities and shareholders' equity	$ 12,273.0	$ 11,104.0