Stock-Based Compensation and Other Employee Benefit Plans (Schedule of Non-Cash Stock-Based Compensation Expense and Related Tax Benefits) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]
Non-cash stock-based compensation expense				$ 7,405	$ 6,320
Income Tax Effects:
Income tax benefit from non-cash stock-based compensation		$ 2,300	$ 1,300	3,900	2,500
Excess tax benefit from non-cash stock-based compensation	[1]	900	100	1,132	53
General and Administrative Expenses [Member]
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]
Non-cash stock-based compensation expense		$ 3,900	$ 2,700	$ 7,400	$ 6,300

[1] Excess tax benefits, which represent cash flows from tax deductions in excess of the tax effect of compensation expense associated with exercised stock options and vested restricted shares, are classified as financing cash flows in the Company’s condensed unaudited consolidated statements of cash flows.