Fair Values - Reconciliation of Beginning and Ending Balances of Assets Measured at Fair Value on Recurring Basis Using Level 3 Inputs (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Adjustments to fair value included in earnings
Valuation allowance on loans held-for-sale	$ (1,300)	$ (1,259)
Other Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance, beginning	54,461
Consolidation of CT Legacy Partners		164,780
Proceeds from investments	(20,231)	(118,635)
Adjustments to fair value included in earnings
Gain on investments at fair value	13,277	7,332
Deferred interest		984
Balance, ending	47,507	54,461
Loans Held-for-Sale, Net [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfer from loans receivable, at fair value		2,000
Proceeds from investments		(3,259)
Adjustments to fair value included in earnings
Valuation allowance on loans held-for-sale		1,259
Investment in CT Legacy Assets [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance, beginning		132,000
Consolidation of CT Legacy Partners		$ (132,000)

Fair value measurement with unobservable inputs reconciliation recurring basis asset transfers net.

No definition available.

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Defined Benefit Plan Asset Deferred Interest

+ References

No definition available.

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- Definition

Consolidations that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

No definition available.

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- Definition

Reversal of provision for loan lease and other losses

+ References

No definition available.

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-03.7(c),9(a))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Section 45

-Paragraph 21

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