CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Cash pledged to creditors	$ 81,640	$ 20,765
Mortgage loans held for sale, pledged to creditors	2,389,066	3,081,987
Servicing advances, net, valuation allowance	65,393	59,958
Servicing advances pledged to creditors	102,222	114,643
Mortgage servicing rights, at fair value	2,785,964	638,010
Mortgage servicing rights pledged to creditors	2,539,575	2,098,067
Furniture, fixtures, equipment and building improvements pledged to creditors	19,022	23,915
Capitalized software pledged to creditors	$ 1,231	$ 1,568
Class A Common Stock
Common stock, shares authorized	200,000,000	200,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares issued	25,195,436	23,529,970
Common stock, shares outstanding	25,195,436	23,529,970
Class B Common Stock
Common stock, shares authorized	1,000	1,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares issued	45	46
Common stock, shares outstanding	45	46