SUBORDINATED DEBENTURES (Details) (USD $) In Thousands, unless otherwise specified			3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 First Bank Statutory Trust II [Member]		Mar. 31, 2013 Royal Oaks Capital Trust I [Member]		Mar. 31, 2013 First Bank Statutory Trust III [Member]		Mar. 31, 2013 First Bank Statutory Trust IV [Member]		Mar. 31, 2013 First Bank Statutory Trust V [Member]		Mar. 31, 2013 First Bank Statutory Trust VI [Member]		Mar. 31, 2013 First Bank Statutory Trust VII [Member]		Mar. 31, 2013 First Bank Statutory Trust VIII [Member]		Mar. 31, 2013 First Bank Statutory Trust X [Member]		Mar. 31, 2013 First Bank Statutory Trust IX [Member]		Mar. 31, 2013 First Bank Statutory Trust XI [Member]		Mar. 31, 2013 First Bank Statutory Trust [Member]		Mar. 31, 2013 First Preferred Capital Trust IV [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust II [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] Royal Oaks Capital Trust I [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust III [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust IV [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust V [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust VI [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust VII [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust VIII [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust X [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust IX [Member]		Mar. 31, 2013 Three-Month London Interbank Offered Rate (LIBOR) [Member] First Bank Statutory Trust XI [Member]
Debt Instrument [Line Items]
Issuance Date			Sep. 01, 2004		Oct. 01, 2004		Nov. 01, 2004		Mar. 01, 2006		Apr. 01, 2006		Jun. 01, 2006		Dec. 01, 2006		Feb. 01, 2007		Aug. 01, 2007		Sep. 01, 2007		Sep. 01, 2007		Mar. 01, 2003		Apr. 01, 2003
Maturity Date			Sep. 20, 2034		Jan. 07, 2035		Dec. 15, 2034		Mar. 15, 2036		Jun. 15, 2036		Jul. 07, 2036		Dec. 15, 2036		Mar. 30, 2037		Sep. 15, 2037		Dec. 15, 2037		Dec. 15, 2037		Mar. 20, 2033		Jun. 30, 2033
Call Date			Sep. 20, 2009	[1]	Jan. 07, 2010	[1]	Dec. 15, 2009	[1]	Mar. 15, 2011	[1]	Jun. 15, 2011	[1]	Jul. 07, 2011	[1]	Dec. 15, 2011	[1]	Mar. 30, 2012	[1]	Sep. 15, 2012	[1]	Dec. 15, 2012	[1]	Dec. 15, 2012	[1]	Mar. 20, 2008	[1]	Jun. 30, 2008	[1]
Debt Instrument, Basis Spread on Variable Rate																													2.05%	[2]	2.40%	[2]	2.18%	[2]	1.42%	[2]	1.45%	[2]	1.65%	[2]	1.85%	[2]	1.61%	[2]	2.30%	[2]	2.25%	[2]	2.85%	[2]
Debt Instrument, Interest Rate, Stated Percentage																									8.10%	[2]	8.15%	[2]
Trust Preferred Securities			$ 20,000		$ 4,000		$ 40,000		$ 40,000		$ 20,000		$ 25,000		$ 50,000		$ 25,000		$ 15,000		$ 25,000		$ 10,000		$ 25,000		$ 46,000
Subordinated debentures	$ 354,153	$ 354,133	$ 20,619		$ 4,124		$ 41,238		$ 41,238		$ 20,619		$ 25,774		$ 51,547		$ 25,774		$ 15,464		$ 25,774		$ 10,310		$ 25,774		$ 47,423

[1] The junior subordinated debentures are callable at the option of the Company on the call date shown at 100% of the principal amount plus accrued and unpaid interest.

[2] The interest rates paid on the trust preferred securities are based on either a variable rate or a fixed rate. The variable rate is based on the three-month LIBOR plus the basis point spread shown.