Depreciation and Amortization (Tables)

12 Months Ended

Dec. 31, 2016

Depreciation And Amortization [Abstract]

Depreciation and Amortization Expense Excluded from Operating Expenses in its Statements of Income

The amounts of depreciation and amortization expense excluded from the following operating expenses in its Statements of Income are:

	Year Ended December 31,
	2016		2015		2014
Direct expenses	$	191,169	$	175,937	$	241,471
General and administrative expenses		3,650		3,178		4,534
Corporate expenses		10,139		12,318		12,430
	$	204,958	$	191,433	$	258,435