Earnings per Share - Composition of Weighted-Average Common Shares (Denominator) Used in Basic and Diluted Earnings Per Share (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Incremental Common Shares Attributable to Call Options and Warrants	0	1,484	0	47
Weighted Average Number of Shares Issued, Basic	105,563,455	105,563,455	105,563,455	105,563,455
Average treasury shares (in shares)	(9,184,715)	(1,258,029)	(7,715,455)	(738,769)
Averaged unearned ESOP shares (in shares)	0	(17,575)	0	(50,790)
Weighted Average Number of Shares, Restricted Stock	(184,146)	(207,826)	(176,657)	(180,771)
Weighted average common shares and common stock equivalents used to calculate basic earnings per share (in shares)	96,194,594	104,080,025	97,671,343	104,593,125
Additional common stock equivalents (nonvested stock) used to calculate diluted earnings per share	13,951	16,874	4,009	2,224
Weighted average common shares and common stock equivalents used to calculate diluted earnings per share (in shares)	96,208,545	104,098,383	97,675,352	104,595,396