Derivatives - Fair Value of Derivative Contracts (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contract, Assets	$ 72,926	$ 92,528
Derivative contract, Liabilities	25,661	16,678
Derivative contract, Notional Amounts	3,271,250	1,814,834
Forward Contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contract, Assets	14,389	8,177
Derivative contract, Liabilities	13,537	9,208
Derivative contract, Notional Amounts	1,606,943	1,213,154
Nasdaq Forwards
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contract, Assets	26,502	77,619
Derivative contract, Liabilities	0	0
Derivative contract, Notional Amounts	267,480	360,960
Rate lock commitments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative contract, Assets	32,035	6,732
Derivative contract, Liabilities	12,124	7,470
Derivative contract, Notional Amounts	$ 1,396,827	$ 240,720

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as a liability.

+ References

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+ References

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