Consolidated Statements of Changes in Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock	Additional Paid-In Capital	Retained Earnings	Noncontrolling Interests	Total
Balances at the beginning of the period at Dec. 31, 2014	$ 318	$ 224,164	$ 208,969		$ 433,451
Balance at the beginning of the period (in shares) at Dec. 31, 2014	31,822
Change in Stockholders' Equity
Walker and Dunlop net income			82,128		82,128
Net income from noncontrolling interests				$ 467	467
Stock-based compensation - equity classified		13,428			13,428
Issuance of common stock in connection with equity compensation plans	$ 8	5,653			5,661
Issuance of common stock in connection with equity compensation plans (in shares)	815
Issuance of unvested restricted common stock in connection with acquisitions		1,892			1,892
Repurchase and retirement of common stock (NOTE 12)	$ (31)	(31,163)	(19,067)		(50,261)
Repurchase and retirement of common stock (NOTE 12) (in shares)	(3,171)
Tax benefit from vesting of restricted shares		1,410			1,410
Noncontrolling interest acquired				4,339	4,339
Other		191		(357)	(166)
Balances at the end of the period at Dec. 31, 2015	$ 295	215,575	272,030	4,449	492,349
Balance at the end of the period (in shares) at Dec. 31, 2015	29,466
Change in Stockholders' Equity
Walker and Dunlop net income			113,897		113,897
Net income from noncontrolling interests				414	414
Stock-based compensation - equity classified		17,616			17,616
Issuance of common stock in connection with equity compensation plans	$ 6	3,759			3,765
Issuance of common stock in connection with equity compensation plans (in shares)	645
Repurchase and retirement of common stock (NOTE 12)	$ (5)	(8,112)	(4,776)		(12,893)
Repurchase and retirement of common stock (NOTE 12) (in shares)	(560)
Other		(84)		(5)	(89)
Balances at the end of the period at Dec. 31, 2016	$ 296	228,889	381,031	4,858	$ 615,074
Balance at the end of the period (in shares) at Dec. 31, 2016	29,551				29,551
Change in Stockholders' Equity
Cumulative effect from change in accounting for stock compensation		135	(120)		$ 15
Walker and Dunlop net income			211,127		211,127
Net income from noncontrolling interests				707	707
Stock-based compensation - equity classified		19,973			19,973
Issuance of common stock in connection with equity compensation plans	$ 12	3,001			3,013
Issuance of common stock in connection with equity compensation plans (in shares)	1,272
Repurchase and retirement of common stock (NOTE 12)	$ (8)	(22,676)	(12,215)		(34,899)
Repurchase and retirement of common stock (NOTE 12) (in shares)	(807)
Other		(14)			(14)
Balances at the end of the period at Dec. 31, 2017	$ 300	$ 229,173	$ 579,943	$ 5,565	$ 814,981
Balance at the end of the period (in shares) at Dec. 31, 2017	30,016				30,016