Net Cash (Received) Paid in Acquisitions and Divestitures (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair value of assets and liabilities acquired:
Net cash (received) paid in acquisitions	$ (178,604)	$ 697	$ (152,283)
Greenpoint
Fair value of assets and liabilities acquired:
Investments			62,919
Loans	140	281	419,320
Premises and equipment	4,547		7,535
Other assets	4,563		255,924
Deposits	(318,877)		(649,184)
Other liabilities	(76)		(60,085)
Purchase price in excess of net assets acquired	1,721	663	21,810
Total purchase price	(307,982)	944	58,239
Non-cash purchase price		247	26,469
Cash acquired			184,053
Net cash (received) paid in acquisitions	(307,982)	697	(152,283)
Book value of assets sold	(83,283)
Book value of liabilities sold	215,268
Sales price in excess of net liabilities assumed	(755)
Total sales price	131,230
Cash sold	(1,852)
Net cash paid (received) in divestitures	$ 129,378

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash.

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Amount of investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Reduction in cash due to no longer including the former subsidiary's cash in the consolidated entity's cash.

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