Condensed Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenues	$ 542,208	$ 416,454
Costs and Expenses:
Cost of operations	392,443	303,635
Research and development costs	4,603	5,174
Selling, general and administrative expenses	52,958	51,683
Total Costs and Expenses	450,004	360,492
Equity in Income of Investees	6,063	7,682
Operating Income	98,267	63,644
Other Income (Expense):
Interest income	231	415
Interest expense	(7,967)	(8,703)
Other – net	7,917	7,521
Total Other Income (Expense)	181	(767)
Income before Provision for Income Taxes	98,448	62,877
Provision for Income Taxes	22,828	13,767
Net Income	75,620	49,110
Net Income Attributable to Noncontrolling Interest	(121)	(132)
Net Income Attributable to BWX Technologies, Inc.	$ 75,499	$ 48,978
Basic:
Net Income Attributable to BWX Technologies, Inc. (in usd per share)	$ 0.79	$ 0.51
Diluted:
Net Income Attributable to BWX Technologies, Inc. (in usd per share)	$ 0.79	$ 0.51
Shares used in the computation of earnings per share (Note 10):
Basic (in shares)	95,412,351	95,255,109
Diluted (in shares)	95,756,372	95,821,354