Loans Receivable and Allowance for Loan Losses - Allowance for Credit Losses on Financing Receivables (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	$ 65,699	$ 73,268	$ 67,320	$ 66,941
Provision (credit) for loan losses	2,996	800	6,022	8,306
Loans charged off	(2,771)	(2,900)	(8,034)	(4,329)
Recoveries of charged offs	946	507	1,562	757
Balance, end of period	66,870	71,675	66,870	71,675
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	9,741		9,741		12,666
Allowance for loan losses - Collectively evaluated for impairment	51,249		51,249		49,876
Allowance for loan losses - ACILS	5,880		5,880		4,778
Allowance for loan losses - Total	66,870	71,675	66,870	71,675
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	124,158		124,158		116,269
Loans outstanding - Collectively evaluated for impairment	5,021,710		5,021,710		4,734,767
Loans outstanding - ACILs	202,448		202,448		225,307
Total loans outstanding	5,348,316		5,348,316		5,076,343
Legacy
Loans outstsanding:
Total loans outstanding	4,529,895		4,529,895		4,097,662
Acquired
Loans outstsanding:
Total loans outstanding	818,421		818,421		978,681
Real estate
Loans outstsanding:
Total loans outstanding	4,184,298		4,184,298		3,904,058
Real estate | Legacy
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	38,586	43,709	40,068	41,505
Provision (credit) for loan losses	1,066	(1,057)	(348)	2,012
Loans charged off	(726)	(777)	(813)	(1,682)
Recoveries of charged offs	132	57	151	97
Balance, end of period	39,058	41,932	39,058	41,932
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	3,394		3,394		5,578
Allowance for loan losses - Collectively evaluated for impairment	35,664		35,664		34,490
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	39,058	41,932	39,058	41,932
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	53,937		53,937		49,177
Loans outstanding - Collectively evaluated for impairment	3,470,699		3,470,699		3,076,924
Loans outstanding - ACILs	0		0		0
Total loans outstanding	3,524,636		3,524,636		3,126,101
Real estate | Acquired
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	6,838	9,889	6,482	4,718
Provision (credit) for loan losses	622	(233)	1,073	5,087
Loans charged off	(188)	(24)	(283)	(175)
Recoveries of charged offs	17	0	17	2
Balance, end of period	7,289	9,632	7,289	9,632
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	431		431		1,092
Allowance for loan losses - Collectively evaluated for impairment	978		978		612
Allowance for loan losses - ACILS	5,880		5,880		4,778
Allowance for loan losses - Total	7,289	9,632	7,289	9,632
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	19,365		19,365		19,992
Loans outstanding - Collectively evaluated for impairment	507,900		507,900		613,696
Loans outstanding - ACILs	132,397		132,397		144,269
Total loans outstanding	659,662		659,662		777,957
Commercial business
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period					17,592
Balance, end of period	15,298		15,298		17,592
Allowance for loan losses:
Allowance for loan losses - Total	15,298		15,298		17,592
Loans outstsanding:
Total loans outstanding	929,143		929,143		949,093
Commercial business | Legacy
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	16,208	16,522	16,796	16,490
Provision (credit) for loan losses	(336)	1,043	2,211	1,082
Loans charged off	(1,794)	(1,413)	(5,519)	(1,596)
Recoveries of charged offs	581	368	1,171	544
Balance, end of period	14,659	16,520	14,659	16,520
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	3,225		3,225		5,183
Allowance for loan losses - Collectively evaluated for impairment	11,434		11,434		11,613
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	14,659	16,520	14,659	16,520
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	37,546		37,546		37,314
Loans outstanding - Collectively evaluated for impairment	793,559		793,559		778,350
Loans outstanding - ACILs	0		0		0
Total loans outstanding	831,105		831,105		815,664
Commercial business | Acquired
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	593	809	796	1,115
Provision (credit) for loan losses	88	484	1,099	295
Loans charged off	(45)	(684)	(1,265)	(808)
Recoveries of charged offs	3	45	9	52
Balance, end of period	639	654	639	654
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	393		393		622
Allowance for loan losses - Collectively evaluated for impairment	246		246		174
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	639	654	639	654
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	2,867		2,867		2,792
Loans outstanding - Collectively evaluated for impairment	56,393		56,393		84,325
Loans outstanding - ACILs	38,778		38,778		46,312
Total loans outstanding	98,038		98,038		133,429
Trade finance
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period					2,653
Balance, end of period	4,568		4,568		2,653
Allowance for loan losses:
Allowance for loan losses - Total	4,568		4,568		2,653
Loans outstsanding:
Total loans outstanding	141,053		141,053		124,685
Trade finance | Legacy
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	2,944	1,698	2,653	2,349
Provision (credit) for loan losses	1,624	637	1,972	12
Loans charged off	0	0	(57)	(26)
Recoveries of charged offs	0	0	0	0
Balance, end of period	4,568	2,335	4,568	2,335
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	2,298		2,298		159
Allowance for loan losses - Collectively evaluated for impairment	2,270		2,270		2,494
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	4,568	2,335	4,568	2,335
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	8,985		8,985		5,692
Loans outstanding - Collectively evaluated for impairment	128,930		128,930		117,249
Loans outstanding - ACILs	0		0		0
Total loans outstanding	137,915		137,915		122,941
Trade finance | Acquired
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	0	0	0	3
Provision (credit) for loan losses	0	0	0	(3)
Loans charged off	0	0	0	0
Recoveries of charged offs	0	0	0	0
Balance, end of period	0	0	0	0
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	0		0		0
Allowance for loan losses - Collectively evaluated for impairment	0		0		0
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	0	0	0	0
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	0		0		0
Loans outstanding - Collectively evaluated for impairment	0		0		0
Loans outstanding - ACILs	3,138		3,138		1,744
Total loans outstanding	3,138		3,138		1,744
Consumer and other
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period					525
Balance, end of period	657		657		525
Allowance for loan losses:
Allowance for loan losses - Total	657		657		525
Loans outstsanding:
Total loans outstanding	93,822		93,822		98,507
Consumer and other | Legacy
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	467	538	461	658
Provision (credit) for loan losses	(69)	(20)	(62)	(149)
Loans charged off	(18)	(2)	(19)	(9)
Recoveries of charged offs	211	12	211	28
Balance, end of period	591	528	591	528
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	0		0		32
Allowance for loan losses - Collectively evaluated for impairment	591		591		429
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	591	528	591	528
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	516		516		535
Loans outstanding - Collectively evaluated for impairment	35,723		35,723		32,421
Loans outstanding - ACILs	0		0		0
Total loans outstanding	36,239		36,239		32,956
Consumer and other | Acquired
Allowance for Loan Losses by Portfolio Segment
Balance, beginning of period	63	103	64	103
Provision (credit) for loan losses	1	(54)	77	(30)
Loans charged off	0	0	(78)	(33)
Recoveries of charged offs	2	25	3	34
Balance, end of period	66	74	66	74
Allowance for loan losses:
Allowance for loan losses - Individually evaluated for impairment	0		0		0
Allowance for loan losses - Collectively evaluated for impairment	66		66		64
Allowance for loan losses - ACILS	0		0		0
Allowance for loan losses - Total	66	74	66	74
Loans outstsanding:
Loans outstanding - Individually evaluated for impairment	942		942		767
Loans outstanding - Collectively evaluated for impairment	28,506		28,506		31,802
Loans outstanding - ACILs	28,135		28,135		32,982
Total loans outstanding	$ 57,583		$ 57,583		$ 65,551