Consolidated Statement of Stockholders' Equity (unaudited) - 6 months ended Jun. 30, 2017 - USD ($) $ in Millions	Total		Common Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock	Trinity Stockholders’ Equity	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2016			152,200,000				100,000
Beginning balance at Dec. 31, 2016	$ 4,311.1		$ 1.6	$ 534.6	$ 3,497.3	$ (113.5)	$ (1.5)	$ 3,918.5	$ 392.6
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	105.7				97.1			97.1	8.6
Other comprehensive income	4.3					2.8		2.8	1.5
Cash dividends on common stock	(36.4)				(36.4)			(36.4)
Restricted shares, net, (in shares)			1,600,000				(600,000)
Restricted shares, net	$ (0.4)		$ 0.0	15.6			$ (16.0)	(0.4)
Shares repurchased (in shares)	(1,942,200)						(1,900,000)
Shares repurchased	$ (52.4)						$ (52.4)	(52.4)
Stock options exercised (in shares)			0
Stock options exercised	0.2		$ 0.0	0.2				0.2
Disbursements to non-controlling interest	(16.9)							0.0	(16.9)
Retirement of treasury stock (shares)			(2,500,000)				(2,500,000)
Retirement of treasury stock	0.0		$ 0.0	(68.3)			$ (68.3)	0.0
Other	0.3			0.9	(0.6)		$ 0.0	0.3
Ending balance (in shares) at Jun. 30, 2017			151,300,000				100,000
Ending balance at Jun. 30, 2017	$ 4,315.5	[1]	$ 1.6	$ 483.0	$ 3,557.4	$ (110.7)	$ (1.6)	$ 3,929.7	$ 385.8

[1] (unaudited)