Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

The cumulative effect of the changes to the Company’s Consolidated Balance Sheets as a result of adopting the new guidance was as follows:



(in thousands)	Balance as of December 31, 2017		Adjustments			Balance as of January 1, 2018
Assets
Accounts receivable, net	$	620,319	$	2,142		$	622,461
Inventories and contracts in progress	60,612		246			60,858
Other current assets	66,253		6,343			72,596
Liabilities
Accounts payable and accrued liabilities	$	526,323	$	88		$	526,411
Deferred revenue	339,454		(346		)	339,108
Deferred income taxes	362,701		2,066			364,767
Equity
Retained earnings	$	5,791,724	$	6,923		$	5,798,647

The effect of these changes to the Consolidated Statements of Operations for 2017 and 2016 is as follows:



(in thousands)	As Previously Reported		Adjustment			Upon Adoption
Year Ended December 31, 2017
Operating expenses	$	1,359,842	$	94,501		$	1,454,343
Selling, general and administrative expenses	909,592		(21,802		)	887,790
Income from Operations	209,102		(72,699		)	136,403
Non-operating pension and postretirement benefit income, net	—		72,699			72,699
Income Before Income Taxes	182,789		—			182,789

Year Ended December 31, 2016
Operating expenses	$	1,180,945	$	89,085		$	1,270,030
Selling, general and administrative expenses	904,517		(8,420		)	896,097
Income from Operations	303,534		(80,665		)	222,869
Non-operating pension and postretirement benefit income, net	—		80,665			80,665
Income Before Income Taxes	250,658		—			250,658