Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Schedule of Reconciliation of the Numerators and Denominators Used in the Basic and Diluted Per-Share Computations

A reconciliation of the numerators and denominators used in the basic and diluted per-share computations is presented as follows for each class of common stock:

(dollars in thousands, except per share data)						For the years ended December 31,
	2019					2018					2017
	Allocated net income (numerator)		Weighted shares (denominator)	Per- share amount		Allocated net income (numerator)		Weighted shares (denominator)	Per- share amount		Allocated net income (numerator)		Weighted shares (denominator)	Per- share amount
Class A – Basic EPS:
Income available to  Class A stockholders	$	314,227	46,188,836	$	6.80	$	285,864	46,188,637	$	6.19	$	195,386	46,186,831	$	4.23
Dilutive effect of stock-based awards	0		30,224	—		0		25,776	—		0		49,832	—
Assumed conversion of Class B shares	2,594		6,100,800	—		2,360		6,100,800	—		1,613		6,100,800	—
Class A – Diluted EPS:
Income available to Class A stockholders on Class A equivalent shares	$	316,821	52,319,860	$	6.06	$	288,224	52,315,213	$	5.51	$	196,999	52,337,463	$	3.76
Class B – Basic EPS:
Income available to Class B stockholders	$	2,594	2,542	$	1,020	$	2,360	2,542	$	928	$	1,613	2,542	$	635
Class B – Diluted EPS:
Income available to Class B stockholders	$	2,593	2,542	$	1,020	$	2,359	2,542	$	928	$	1,613	2,542	$	634