Loans (Balances Of Commercial Loan Portfolio Classes, Disaggregated By PD Grade) (Details) $ in Thousands		Sep. 30, 2016 USD ($) number	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($) number	Jun. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses		$ 201,557	$ 199,807	$ 210,242	$ 210,814	$ 221,351	$ 232,448
Total loans collectively evaluated for impairment		19,192,515			16,372,366
Total loans individually evaluated for impairment		305,973			325,470
Allowance - collectively evaluated for impairment		150,777			151,370
Allowance - individually evaluated for impairment		49,614			56,525
Allowance - purchased credit impaired loans		1,166			2,919
Purchase credit impaired loans - recorded investment		57,299			27,656
General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans collectively evaluated for impairment		9,238,111			7,884,924
Total loans individually evaluated for impairment		46,109			26,904
Total commercial loans		9,330,710			7,916,838
Purchase credit impaired loans - recorded investment		46,490			5,010
Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans collectively evaluated for impairment		2,479,819			1,375,320
Total loans individually evaluated for impairment		0			0
Total commercial loans		2,479,819			1,375,320
Purchase credit impaired loans - recorded investment		0			0
TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans collectively evaluated for impairment	[1]	304,527			305,382
Total loans individually evaluated for impairment	[1]	3,242			12,755
Total commercial loans	[1]	307,769			318,137
LOCOM valuation allowance		$ 25,500			$ 26,200
Highest internal grade | number		13			13
Purchase credit impaired loans - recorded investment	[1]	$ 0			$ 0
Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans collectively evaluated for impairment		2,002,248			1,437,000
Total loans individually evaluated for impairment		1,968			8,892
Total commercial loans		2,012,974			1,464,425
Purchase credit impaired loans - recorded investment		8,758			18,533
Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans collectively evaluated for impairment		50,853			20,568
Total loans individually evaluated for impairment		1,334			1,417
Total commercial loans		52,621			23,619
Purchase credit impaired loans - recorded investment		$ 434			$ 1,634
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percent of total commercial loans		100.00%			100.00%
Allowance for loan losses		$ 119,286			$ 96,811
Total loans collectively evaluated for impairment		14,075,558			11,023,194
Total loans individually evaluated for impairment		52,653			49,968
Total commercial loans		14,183,893			11,098,339
Allowance - collectively evaluated for impairment		113,050			87,654
Allowance - individually evaluated for impairment		5,403			6,743
Allowance - purchased credit impaired loans		$ 833			$ 2,414
Percent of loan collectively evaluated for impairment		99.00%			99.00%
Percent of loan individually evaluated for impairment		0.00%			1.00%
Purchase credit impaired loans - recorded investment		$ 55,682			$ 25,177
Percent of loan purchased-credit impaired		1.00%			0.00%
Commercial Loan P D Grade One [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 476,817			$ 530,543
Percent of total commercial loans		3.00%			5.00%
Allowance for loan losses		$ 85			$ 127
Commercial Loan P D Grade One [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		475,708			529,836
Commercial Loan P D Grade One [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade One [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade One [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		1,109			707
Commercial Loan P D Grade One [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade Two [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 701,297			$ 601,575
Percent of total commercial loans		5.00%			5.00%
Allowance for loan losses		$ 332			$ 322
Commercial Loan P D Grade Two [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		689,620			590,614
Commercial Loan P D Grade Two [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade Two [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Two [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		11,586			10,835
Commercial Loan P D Grade Two [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		91			126
Commercial Loan P D Grade Three [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 1,225,257			$ 872,195
Percent of total commercial loans		9.00%			8.00%
Allowance for loan losses		$ 298			$ 311
Commercial Loan P D Grade Three [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		445,832			453,831
Commercial Loan P D Grade Three [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		645,764			327,776
Commercial Loan P D Grade Three [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Three [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		133,661			90,588
Commercial Loan P D Grade Three [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade Four [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 1,563,933			$ 1,248,043
Percent of total commercial loans		11.00%			11.00%
Allowance for loan losses		$ 1,001			$ 949
Commercial Loan P D Grade Four [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		924,003			822,515
Commercial Loan P D Grade Four [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		409,470			315,061
Commercial Loan P D Grade Four [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Four [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		230,460			110,165
Commercial Loan P D Grade Four [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			302
Commercial Loan P D Grade Five [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 1,734,952			$ 1,671,220
Percent of total commercial loans		12.00%			15.00%
Allowance for loan losses		$ 6,330			$ 6,901
Commercial Loan P D Grade Five [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		1,148,228			1,190,085
Commercial Loan P D Grade Five [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		286,413			239,391
Commercial Loan P D Grade Five [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Five [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		299,750			234,729
Commercial Loan P D Grade Five [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		561			7,015
Commercial Loan P D Grade Six [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 2,490,704			$ 1,902,487
Percent of total commercial loans		18.00%			17.00%
Allowance for loan losses		$ 10,367			$ 10,630
Commercial Loan P D Grade Six [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		1,417,978			1,201,553
Commercial Loan P D Grade Six [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		762,294			350,401
Commercial Loan P D Grade Six [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Six [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		297,287			347,740
Commercial Loan P D Grade Six [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		13,145			2,793
Commercial Loan P D Grade Seven [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 2,123,398			$ 1,735,832
Percent of total commercial loans		15.00%			16.00%
Allowance for loan losses		$ 13,302			$ 13,891
Commercial Loan P D Grade Seven [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		1,431,070			1,278,443
Commercial Loan P D Grade Seven [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		209,511			98,262
Commercial Loan P D Grade Seven [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Seven [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		479,531			354,457
Commercial Loan P D Grade Seven [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		3,286			4,670
Commercial Loan P D Grade Eight [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 1,415,455			$ 916,885
Percent of total commercial loans		10.00%			8.00%
Allowance for loan losses		$ 23,930			$ 13,953
Commercial Loan P D Grade Eight [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		995,678			747,760
Commercial Loan P D Grade Eight [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		93,661			18,189
Commercial Loan P D Grade Eight [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Eight [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		321,942			150,375
Commercial Loan P D Grade Eight [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		4,174			561
Commercial Loan P D Grade Nine [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 776,032			$ 449,445
Percent of total commercial loans		5.00%			4.00%
Allowance for loan losses		$ 14,419			$ 8,310
Commercial Loan P D Grade Nine [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		634,142			377,998
Commercial Loan P D Grade Nine [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		32,537			26,240
Commercial Loan P D Grade Nine [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Nine [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		105,274			42,995
Commercial Loan P D Grade Nine [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		4,079			2,212
Commercial Loan P D Grade Ten [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 478,282			$ 219,315
Percent of total commercial loans		3.00%			2.00%
Allowance for loan losses		$ 8,401			$ 4,635
Commercial Loan P D Grade Ten [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		367,947			188,711
Commercial Loan P D Grade Ten [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		40,099			0
Commercial Loan P D Grade Ten [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Ten [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		57,528			30,515
Commercial Loan P D Grade Ten [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		12,708			89
Commercial Loan P D Grade Eleven [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 247,531			$ 215,725
Percent of total commercial loans		2.00%			2.00%
Allowance for loan losses		$ 6,229			$ 5,861
Commercial Loan P D Grade Eleven [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		218,754			186,974
Commercial Loan P D Grade Eleven [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade Eleven [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Eleven [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		24,245			28,004
Commercial Loan P D Grade Eleven [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		4,532			747
Commercial Loan P D Grade Twelve [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 137,804			$ 90,447
Percent of total commercial loans		1.00%			1.00%
Allowance for loan losses		$ 4,290			$ 2,975
Commercial Loan P D Grade Twelve [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		118,425			80,836
Commercial Loan P D Grade Twelve [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade Twelve [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Twelve [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		12,678			9,095
Commercial Loan P D Grade Twelve [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		6,701			516
Commercial Loan P D Grade Thirteen [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 529,966			$ 421,665
Percent of total commercial loans		4.00%			4.00%
Allowance for loan losses		$ 7,262			$ 4,256
Commercial Loan P D Grade Thirteen [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		216,314			112,423
Commercial Loan P D Grade Thirteen [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		0			0
Commercial Loan P D Grade Thirteen [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	304,527			305,382
Commercial Loan P D Grade Thirteen [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		8,990			3,600
Commercial Loan P D Grade Thirteen [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		135			260
Commercial Loan P D Grade Fourteen Fifteen Sixteen [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 174,130			$ 147,817
Percent of total commercial loans		1.00%			1.00%
Allowance for loan losses		$ 16,804			$ 14,533
Commercial Loan P D Grade Fourteen Fifteen Sixteen [Member] | General C I [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		154,412			123,345
Commercial Loan P D Grade Fourteen Fifteen Sixteen [Member] | Loans To Mortgage Companies [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		70			0
Commercial Loan P D Grade Fourteen Fifteen Sixteen [Member] | TRUPs [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade	[1]	0			0
Commercial Loan P D Grade Fourteen Fifteen Sixteen [Member] | Income C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		18,207			23,195
Commercial Loan P D Grade Fourteen Fifteen Sixteen [Member] | Residential C R E [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loan, Disaggregated by PD grade		$ 1,441			$ 1,277

[1] Balances as of September 30 , 2016 and 2015 , presented net of $ 25.5 million and $ 26.2 million, respectively, in lower of cost or market (“LOCOM”) valuation adjustment . Based on the underlying structure of the notes , the highest possible internal grade is " 13 ".