Document and Entity Information	6 Months Ended
	Jun. 30, 2019 shares
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Registrant Name	NAVIGANT CONSULTING INC
Entity Central Index Key	0001019737
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	38,466,024
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Trading Symbol	NCI
Title of 12(b) Security	Common Stock, $0.001 parvalue per share
Security Exchange Name	NYSE
Entity File Number	1-12173
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-4094854
Entity Address, Address Line One	150 North Riverside Plaza
Entity Address, Address Line Two	Suite 2100
Entity Address, City or Town	Chicago
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60606
City Area Code	(312)
Local Phone Number	573-5600
Document Quarterly Report	true
Document Transition Report	false