STOCKHOLDERS' EQUITY - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 01, 2017	Dec. 05, 2016
Class Of Stock [Line Items]
Common stock, shares authorized		2,000,000,000	2,000,000,000
Common stock, par value		$ 0.1	$ 0.1
Common stock, shares issued		218,700,394	216,051,128
Common stock, shares outstanding		217,446,205	215,088,698
Granted shares of restricted stock		1,925,575
Corporation has authorized shares of preferred stock		50,000,000	50,000,000
Preferred stock, par value		$ 1
Liquidation value per share		$ 25
Repurchased of common stock		291,759	222,381
Treasury Stock Shares		1,254,189	962,430
Secondary Offering Of Common Stock					23,000,000
Purchase Of Common Stock Secondary Offering						2,700,000
Conversion Of Stock Shares Issued1	852,831			4,597,121
Legal Surplus Amount		$ 52,436	$ 42,798
Shares Of Preferred Stock Exchanged				1,077,726
Legal Surplus Amount Additions		$ 9,600	$ 2,800
Junior Subordinated Debt [Member]
Class Of Stock [Line Items]
Increase Decrease In Securities Borrowed	$ (5,500)
Minimum [Member]
Class Of Stock [Line Items]
Legal surplus reserve rate		10.00%
Omnibus Plan [Member]
Class Of Stock [Line Items]
Restricted stock granted to senior executive officers		6,846,986
Restricted Stock [Member]
Class Of Stock [Line Items]
Repurchased of common stock		65,498	72,918
Forefeited		31,532
Number of vested shares		683,713
Thomas H Lee Partners [Member]
Class Of Stock [Line Items]
Percentage Of Stock Ownership		14.50%			9.20%
Secondary Offering Of Common Stock						9,000,000
Oaktree Capital Management [Member]
Class Of Stock [Line Items]
Percentage Of Stock Ownership		14.50%			9.20%
Secondary Offering Of Common Stock						9,000,000
7.125% Noncumulative Perpetual Monthly Income Preferred Stock, Series A [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage		7.125%
8.35% Noncumulative Perpetual Monthly Income Preferred Stock, Series B [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage		8.35%
7.40% Noncumulative Perpetual Monthly Income Preferred Stock, Series C [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage		7.40%
7.25% Noncumulative Perpetual Monthly Income Preferred Stock, Series D [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage		7.25%
7.00% Noncumulative Perpetual Monthly Income Preferred Stock, Series E [Member]
Class Of Stock [Line Items]
Preferred stock dividend rate percentage		7.00%