\documentclass[11pt]{article}

\usepackage[utf8]{inputenc}
\usepackage{array}
\usepackage{amssymb, mathtools}

\usepackage{arydshln}
\setlength\dashlinedash{2pt}
\setlength\dashlinegap{1.2pt}

\newenvironment{BMatrix}[1]{%
\Bmatrix\hspace{-0.5\arraycolsep}\array{#1}}%
{\endarray\hspace*{-0.5\arraycolsep}\endBmatrix}
\newenvironment{bMatrix}[1]{%
\bmatrix\array{#1}\hspace*{-0.5\arraycolsep}}%
{\endarray\endbmatrix}

\begin{document}

\[  \begin{BMatrix}{r}%{c}%
  N \\ \hdashline MM
  \end{BMatrix}
  =\begin{bMatrix}{c:c}
  A & B \\ \hdashline C & D
  \end{bMatrix}
  \begin{BMatrix}{c}\epsilon^D \\ \hdashline k \end{BMatrix} \]%

\end{document}