Loans and Allowance for Loan and Lease Losses (Schedule of Commercial Credit Exposure Based on Internal Risk Ratings) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	$ 23,154,988	$ 21,977,008
Multi-family
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	2,217,705	2,585,421
Multi-family | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	2,184,771	2,547,835
Multi-family | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	2,932
Multi-family | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	32,934	34,654
Multi-family | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Commercial real estate, Non-owner occupied
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	5,030,904	4,688,880
Commercial real estate, Non-owner occupied | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	4,932,279	4,611,029
Commercial real estate, Non-owner occupied | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	5,831	16,516
Commercial real estate, Non-owner occupied | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	92,794	61,335
Commercial real estate, Non-owner occupied | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Construction and land
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	243,925	226,840
Construction and land | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	240,734	216,917
Construction and land | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	0
Construction and land | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	3,191	9,923
Construction and land | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Commercial real estate, Owner occupied
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	2,062,808	2,119,880
Commercial real estate, Owner occupied | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	1,991,556	2,077,611
Commercial real estate, Owner occupied | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	27,870	13,368
Commercial real estate, Owner occupied | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	43,382	28,901
Commercial real estate, Owner occupied | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Commercial and Industrial Sector [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	4,655,349	4,358,526
Commercial and Industrial Sector [Member] | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	4,508,563	4,285,478
Commercial and Industrial Sector [Member] | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	28,498	27,611
Commercial and Industrial Sector [Member] | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	118,288	43,691
Commercial and Industrial Sector [Member] | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		1,746
Pinnacle Public Finance [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	1,202,430	1,462,655
Pinnacle Public Finance [Member] | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	1,202,430	1,462,655
Pinnacle Public Finance [Member] | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	0
Pinnacle Public Finance [Member] | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	0
Pinnacle Public Finance [Member] | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Bridge - franchise finance [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	627,482	517,305
Bridge - franchise finance [Member] | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	562,042	492,853
Bridge - franchise finance [Member] | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	10,682	9,232
Bridge - franchise finance [Member] | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	54,758	15,220
Bridge - franchise finance [Member] | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Bridge - equipment finance [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	684,794	636,838
Bridge - equipment finance [Member] | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	663,855	612,968
Bridge - equipment finance [Member] | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	925
Bridge - equipment finance [Member] | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	20,939	16,302
Bridge - equipment finance [Member] | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		6,643
Mortgage warehouse lending [Member]
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	768,472	431,674
Mortgage warehouse lending [Member] | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	768,472	421,188
Mortgage warehouse lending [Member] | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	10,486
Mortgage warehouse lending [Member] | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	0	0
Mortgage warehouse lending [Member] | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		0
Commercial
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	17,493,869	17,028,019
Commercial | Pass
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	17,054,702	16,728,534
Commercial | Special mention
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	72,881	81,070
Commercial | Substandard
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs	$ 366,286	210,026
Commercial | Doubtful
Financing Receivable Recorded Investment [Line Items]
Loans and lease receivable, net of premiums, discounts and deferred fees and costs		$ 8,389