Recently Issued Accounting Standards Level 4 Balance Sheet Adjustments(details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011		Dec. 31, 2010
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred acquisition costs	$ 56,903	$ 55,467		$ 6,400
Total assets	629,801	604,977
Deferred income taxes	26,023	24,614		2,300
Total liabilities	492,518	477,393
Retained earnings	46,725	35,150		4,200
Non-controlling interest	580	511
Total stockholders' equity	137,283	127,584
Total liabilities and stockholders' equity	629,801	604,977
As Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred acquisition costs		62,687	[1]
Total assets		612,197	[1]
Deferred income taxes		27,141	[1]
Total liabilities		479,920	[1]
Retained earnings		39,822	[1]
Non-controlling interest		532	[1]
Total stockholders' equity		132,277	[1]
Total liabilities and stockholders' equity		612,197	[1]
Effect of the Change [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred acquisition costs		(7,220)
Total assets		(7,220)
Deferred income taxes		(2,527)
Total liabilities		(2,527)
Retained earnings		(4,672)
Non-controlling interest		(21)
Total stockholders' equity		(4,693)
Total liabilities and stockholders' equity		(7,220)
As Restated [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred acquisition costs		55,467
Total assets		604,977
Deferred income taxes		24,614
Total liabilities		477,393
Retained earnings		35,150
Non-controlling interest		511
Total stockholders' equity		127,584
Total liabilities and stockholders' equity		$ 604,977

[1] Includes the business acquisition valuation measurement period adjustments described in Notes 6, 7 and 8.