Consolidated Statement of Changes in Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income
Balance (in shares) at Dec. 31, 2013		41.8
Balance at Dec. 31, 2013	$ 1,183.8	$ 1.0	$ 187.3	$ 3,777.7	$ (3,090.4)	$ 308.2
Comprehensive income:
Net income attributable to DST Systems, Inc.	593.3			593.3
Other comprehensive loss	(121.3)					(121.3)
Dividends	(47.6)		(0.7)	(48.3)
Amortization of share based compensation	21.0		21.0
Issuance of common stock (in shares)		0.5
Issuance of common stock	20.0		8.0		28.0
Repurchase of common stock (in shares)		(4.7)
Repurchase of common stock	(424.5)				(424.5)
Retirement of treasury stock	0.0	$ 0.5	98.3	2,639.8	2,738.6
Other	11.7		11.7
Balance (in shares) at Dec. 31, 2014		37.6
Balance at Dec. 31, 2014	1,236.4	$ 0.5	114.4	1,682.9	(748.3)	186.9
Comprehensive income:
Net income attributable to DST Systems, Inc.	358.2			358.2
Other comprehensive loss	(145.0)					(145.0)
Dividends	(43.1)		(1.4)	(44.5)
Amortization of share based compensation	27.9		27.9
Issuance of common stock (in shares)		0.3
Issuance of common stock	18.7		5.2		23.9
Repurchase of common stock (in shares)		(3.6)
Repurchase of common stock	(405.3)				(405.3)
Other	(1.8)		(1.8)
Balance (in shares) at Dec. 31, 2015		34.3
Balance at Dec. 31, 2015	1,046.0	$ 0.5	136.7	1,996.6	(1,129.7)	41.9
Comprehensive income:
Net income attributable to DST Systems, Inc.	427.3			427.3
Other comprehensive loss	(25.3)					(25.3)
Dividends	(43.4)		(1.3)	(44.7)
Amortization of share based compensation	16.3		16.3
Issuance of common stock (in shares)		0.4
Issuance of common stock	10.4		24.5		34.9
Repurchase of common stock (in shares)		(2.7)
Repurchase of common stock	(315.8)				(315.8)
Other	(0.3)		(0.3)
Balance (in shares) at Dec. 31, 2016		32.0
Balance at Dec. 31, 2016	$ 1,115.2	$ 0.5	$ 129.5	$ 2,379.2	$ (1,410.6)	$ 16.6