Reorganization and Acquisition Activity (Details) (USD $)						9 Months Ended				9 Months Ended								9 Months Ended
	Sep. 30, 2012	Jun. 21, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2012 Class B Non-Voting common stock [Member]	Sep. 30, 2011 Class B Non-Voting common stock [Member]	Mar. 31, 2011 Class B Non-Voting common stock [Member]	Jun. 21, 2012 Acacia federal savings bank acquisition [Member]	Sep. 30, 2012 CMS bancorp acquisition [Member]	Aug. 10, 2012 CMS bancorp acquisition [Member]	Jun. 30, 2012 CMS bancorp acquisition [Member]	Mar. 31, 2012 CMS bancorp acquisition [Member]	Sep. 30, 2012 Outstanding warrants [Member] Class B Non-Voting common stock [Member]	Sep. 30, 2012 Warrants [Member] Class B Non-Voting common stock [Member]	Sep. 30, 2012 Outstanding stock options [Member] Class B Non-Voting common stock [Member]	Sep. 30, 2012 Stock Option [Member] Class B Non-Voting common stock [Member]	Sep. 30, 2012 Common stock [Member]	Sep. 30, 2011 Common stock [Member]	Mar. 31, 2011 Common stock [Member]	Sep. 30, 2012 Common stock [Member] Outstanding warrants [Member]	Sep. 30, 2012 Common stock [Member] Warrants [Member]	Sep. 30, 2012 Common stock [Member] Outstanding stock options [Member]	Sep. 30, 2012 Common stock [Member] Stock Option [Member]
Reorganization and Acquisition Activity (Textual) [Abstract]
Business acquisition consideration ratio						3												3
Common stock authorized issue	200,000,000		200,000,000			100,000,000												100,000,000
Preferred stock authorized issue	100,000,000		100,000,000
Outstanding shares of common stock issued	18,459,502		11,347,683	11,395,604	8,398,015	6,834,895												22,525,825
Shares converted into Bancorp's common stock						2,278,294												7,508,473
Common stock shares issued	18,507,121		11,395,302				565,848	146,310						243,102	81,036	231,500	77,166		419,000	210,916	1,410,732	470,260	2,572,404	855,774
Weighted-average exercise price														$ 3.50	$ 10.50	$ 4.00	$ 12.00				$ 3.55	$ 10.64	$ 3.50	$ 10.49
Total consideration on acquisition									$ 65,000,000		$ 20,800,000
CMS Bank Branches											5
CMS Valuation											95.00%
Customers valuation											125.00%
Book value per share of CMS Bancorp													$ 11.75
Modified stockholders equity of customers Bancorp												$ 13.99
Exchange ratio										0.6383
Reorganization and Acquisition Activity (Additional Textual) [Abstract]
Percentage acquisition of stock		100.00%
Percentage on voting stock held		9.90%
Percentage of ownership on voting stock		19.90%
Aggregate liquidation value		65,000,000
Voting and class B non-voting common stock issued	18,507,000		11,395,000
Percentage on book value of voting and non-voting common stock		115.00%
Issuance of Perpetual Preferred stock	$ 0		$ 0