Consolidated Statements of Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common stock	Additional paid-in capital	Retained earnings	Treasury stock, at cost	Non-controlling interests
Balance at Dec. 31, 2009	$ 86,348	$ 24,145	$ 50,538	$ 11,665
Balance (in shares) at Dec. 31, 2009		24,145,000
Increase (Decrease) in Stockholders' Equity
Net Income	56,174			49,271		6,903
Acquisition of MPA	27,168	959	22,941			3,268
Acquisition of MPA, shares		959,000
Contributions from non-controlling interest holders	41					41
Distributions to non-controlling interest holders	(7,152)					(7,152)
Share-based compensation expense	3,110		3,110
Exercise of stock options	3,986	298	2,708	(2,390)	3,370
Exercise of stock options, shares		298,000
Delivery of vested restricted stock	11	11
Delivery of vested restricted stock, shares		11,000
Repurchase of shares	(17,788)				(17,788)
Balance at Dec. 31, 2010	151,898	25,413	79,297	58,546	(14,418)	3,060
Balance (in shares) at Dec. 31, 2010		25,413,000
Increase (Decrease) in Stockholders' Equity
Net Income	77,967			71,112		6,855
Contributions from non-controlling interest holders	49					49
Distributions to non-controlling interest holders	(6,776)					(6,776)
Share-based compensation expense	3,932		3,932
Exercise of stock options	1,024			(3,497)	4,521
Repurchase of shares	(62,151)				(62,151)
Balance at Dec. 31, 2011	165,943	25,413	83,229	126,161	(72,048)	3,188
Balance (in shares) at Dec. 31, 2011		25,413,000
Increase (Decrease) in Stockholders' Equity
Net Income	115,911			110,627		5,284
Contributions from non-controlling interest holders	43					43
Distributions to non-controlling interest holders	(7,145)					(7,145)
Net assets distributed in connection with the Separation of the Residential Asset Businesses	(105,000)			(105,000)
Share-based compensation expense	3,644		3,644
Exercise of stock options	3,214			(7,661)	10,875
Exercise of stock options, shares	285,054
Repurchase of shares	(16,781)				(16,781)
Balance at Dec. 31, 2012	$ 159,829	$ 25,413	$ 86,873	$ 124,127	$ (77,954)	$ 1,370
Balance (in shares) at Dec. 31, 2012		25,413,000