Equity And Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2016

Equity And Earnings Per Share [Abstract]



	IBG, Inc.	Holdings	Total
Ownership %	16.6%	83.4%	100.0%
Membership interests	67,989,967	341,444,304	409,434,271

Earnings Per Share Basic And Diluted

Basic earnings per share is calculated utilizing net income available for common stockholders divided by the weighted average number of shares of Class A and Class B common stock outstanding for that period.



	Year-Ended December 31,
	2016		2015		2014

	(in millions, except share or per share amounts)
Basic earnings per share
Net income available for common stockholders	$	84	$	49	$	45
Weighted average shares of common stock outstanding
Class A		66,013,147		61,042,971		56,492,281
Class B		100		100		100
		66,013,247		61,043,071		56,492,381
Basic earnings per share	$	1.28	$	0.80	$	0.79

Diluted earnings per share are calculated utilizing the Company’s basic net income available for common stockholders divided by diluted weighted average shares outstanding with no adjustments to net income available to common stockholders for potentially dilutive common shares.



	Year-Ended December 31,
	2016		2015		2014

	(in millions, except share or per share amounts)
Diluted earnings per share
Net income available for common stockholders	$	84	$	49	$	45
Weighted average shares of common stock outstanding
Class A
Issued and outstanding		66,013,147		61,042,971		56,492,281
Potentially dilutive common shares
Issuable pursuant to employee stock incentive plans		1,286,166		1,466,725		1,217,287
Class B		100		100		100
		67,299,413		62,509,796		57,709,668
Diluted earnings per share	$	1.25	$	0.78	$	0.77