General Introduction [Abstract]

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Loans and Leases Receivable Gross Carrying Amount Covered And Noncovered

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Retail Branch Locations

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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The number of businesses acquired by the entity during the period.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The cash inflow associated with the sale or collection of receivables arising from the lease of real estate, equipment or other fixed assets for a specified time in exchange for payment, usually in the form of rent; excludes proceeds from sales-type lease transactions, which are classified as operating activities.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Organization (Details) $ in Thousands		9 Months Ended
Organization (Details) $ in Thousands	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($) acquisition segment bank_branch	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
General Introduction [Abstract]
Assets		$ 21,315,291		$ 21,288,490
Gross loans and leases		14,800,000
Total deposits		15,645,668		15,666,182
Total stockholders' equity		$ 4,542,595		$ 4,397,691
Number of businesses acquired \| acquisition		28
Proceeds from sale of leasing unit		$ (138,955)	$ 0
Number of segments \| segment		1
CapitalSource Inc.
General Introduction [Abstract]
Effective date of acquisition		Apr. 07, 2014
PWEF
General Introduction [Abstract]
Proceeds from sale of leasing unit	$ (139,000)
CALIFORNIA
General Introduction [Abstract]
Retail branch locations \| bank_branch		79
NORTH CAROLINA
General Introduction [Abstract]
Retail branch locations \| bank_branch		1