BANK LOANS, NET, Allowance for Loan Losses, Loans Individually and Collectively Evaluated for Impairment (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013
Allowance for loan losses:
Individually evaluated for impairment	$ 5,596,000		$ 6,301,000
Collectively evaluated for impairment	154,412,000		141,273,000
Total allowance for loan losses	160,008,000	156,767,000	147,574,000	137,940,000	138,124,000	136,501,000
Recorded investment:
Individually evaluated for impairment	87,606,000		96,628,000
Collectively evaluated for impairment	12,079,182,000		11,006,790,000
Total loans held for investment	12,166,788,000		11,103,418,000
Tax-exempt loans
Recorded investment:
Total loans held for investment	361,644,000		122,218,000
Loans held for investment | C&I
Allowance for loan losses:
Individually evaluated for impairment	1,220,000		1,289,000
Collectively evaluated for impairment	109,905,000		101,890,000
Total allowance for loan losses	111,125,000	109,582,000	103,179,000	95,702,000	96,629,000	95,994,000
Recorded investment:
Individually evaluated for impairment	11,418,000		11,959,000
Collectively evaluated for impairment	6,801,782,000		6,410,388,000
Total loans held for investment	6,813,200,000		6,422,347,000
Loans held for investment | CRE construction
Allowance for loan losses:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	1,675,000		1,594,000
Total allowance for loan losses	1,675,000	1,709,000	1,594,000	1,799,000	1,647,000	1,000,000
Recorded investment:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	100,914,000		94,195,000
Total loans held for investment	100,914,000		94,195,000
Loans held for investment | CRE
Allowance for loan losses:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	25,717,000		25,022,000
Total allowance for loan losses	25,717,000	25,095,000	25,022,000	22,276,000	20,210,000	19,266,000
Recorded investment:
Individually evaluated for impairment	17,171,000		18,876,000
Collectively evaluated for impairment	1,655,774,000		1,670,287,000
Total loans held for investment	1,672,945,000		1,689,163,000
Loans held for investment | Tax-exempt loans
Allowance for loan losses:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	3,909,000		1,380,000
Total allowance for loan losses	3,909,000	2,738,000	1,380,000	0	0	0
Recorded investment:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	361,644,000		122,218,000
Total loans held for investment	361,644,000		122,218,000
Loans held for investment | Residential mortgage
Allowance for loan losses:
Individually evaluated for impairment	4,376,000		5,012,000
Collectively evaluated for impairment	10,700,000		9,338,000
Total allowance for loan losses	15,076,000	15,319,000	14,350,000	16,614,000	18,300,000	19,126,000
Recorded investment:
Individually evaluated for impairment	59,017,000		65,793,000
Collectively evaluated for impairment	1,907,184,000		1,685,954,000
Total loans held for investment	1,966,201,000		1,751,747,000
Loans held for investment | SBL and other consumer
Allowance for loan losses:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	2,506,000		2,049,000
Total allowance for loan losses	2,506,000	2,324,000	2,049,000	1,549,000	1,338,000	1,115,000
Recorded investment:
Individually evaluated for impairment	0		0
Collectively evaluated for impairment	1,251,884,000		1,023,748,000
Total loans held for investment	1,251,884,000		1,023,748,000
RJ Bank
Reserve for unfunded lending commitments [Abstract]
Reserve for unfunded lending commitments	$ 13,200,000		$ 10,000,000