Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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Loans Receivable and Allowance for Credit Losses (Summary of Activities in Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Allowance for loan losses
Beginning balance			$ 287,128
Charge-offs	$ (13,300)	$ (117)	(13,400)	$ (209)
Ending balance	301,550	276,316	301,550	276,316
Commercial lending \| Commercial and industrial (“C&I”)
Allowance for loan losses
Beginning balance			163,058
Ending balance	162,404		162,404
Commercial lending \| Commercial real estate (“CRE”)
Allowance for loan losses
Beginning balance			41,237
Ending balance	44,620		44,620
Commercial lending \| Real estate loan \| Multifamily
Allowance for loan losses
Beginning balance			19,109
Ending balance	18,486		18,486
Commercial lending \| Construction and land
Allowance for loan losses
Beginning balance			26,881
Ending balance	30,362		30,362
Consumer lending \| Real estate loan \| Single-family
Allowance for loan losses
Beginning balance			26,362
Ending balance	33,388		33,388
Consumer lending \| HELOCs
Allowance for loan losses
Beginning balance			7,354
Ending balance	7,277		7,277
Consumer lending \| Other consumer
Allowance for loan losses
Beginning balance			3,127
Ending balance	5,013		5,013
Non-PCI Loans
Allowance for loan losses
Beginning balance	297,607	263,007	287,070	260,402
(Reversal of) provision for loan losses	15,139	10,680	35,072	18,726
Charge-offs	(13,696)	(5,391)	(32,159)	(12,600)
Recoveries	2,461	7,942	11,528	9,710
Net recoveries (charge-offs)	(11,235)	2,551	(20,631)	(2,890)
Ending balance	301,511	276,238	301,511	276,238
Non-PCI Loans \| Commercial lending \| Commercial and industrial (“C&I”)
Allowance for loan losses
Charge-offs	(13,534)	(5,386)	(31,979)	(12,443)
Recoveries	511	7,038	8,198	7,493
Non-PCI Loans \| Commercial lending \| Commercial real estate (“CRE”)
Allowance for loan losses
Recoveries	2	423	429	992
Non-PCI Loans \| Commercial lending \| Real estate loan \| Multifamily
Allowance for loan losses
Recoveries	1,061	128	1,394	695
Non-PCI Loans \| Commercial lending \| Construction and land
Allowance for loan losses
Charge-offs	0	(1)	0	(149)
Recoveries	258	88	693	112
Non-PCI Loans \| Consumer lending \| Real estate loan \| Single-family
Allowance for loan losses
Charge-offs	0	(1)	(1)	(1)
Recoveries	629	243	813	254
Non-PCI Loans \| Consumer lending \| HELOCs
Allowance for loan losses
Recoveries	0	0	0	24
Non-PCI Loans \| Consumer lending \| Other consumer
Allowance for loan losses
Charge-offs	(162)	(3)	(179)	(7)
Recoveries	0	22	1	140
PCI Loans
Allowance for loan losses
Beginning balance	47	87	58	118
(Reversal of) provision for loan losses	(8)	(9)	(19)	(40)
Ending balance	39	$ 78	39	$ 78
PCI Loans \| Commercial lending \| Commercial and industrial (“C&I”)
Allowance for loan losses
Beginning balance			0
Ending balance	0		0
PCI Loans \| Commercial lending \| Commercial real estate (“CRE”)
Allowance for loan losses
Beginning balance			58
Ending balance	39		39
PCI Loans \| Commercial lending \| Real estate loan \| Multifamily
Allowance for loan losses
Beginning balance			0
Ending balance	0		0
PCI Loans \| Commercial lending \| Construction and land
Allowance for loan losses
Beginning balance			0
Ending balance	0		0
PCI Loans \| Consumer lending \| Real estate loan \| Single-family
Allowance for loan losses
Beginning balance			0
Ending balance	0		0
PCI Loans \| Consumer lending \| HELOCs
Allowance for loan losses
Beginning balance			0
Ending balance	0		0
PCI Loans \| Consumer lending \| Other consumer
Allowance for loan losses
Beginning balance			0
Ending balance	$ 0		$ 0