Fair Value - Measured on Recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	$ 1,538,880		$ 1,513,157
Loans receivable, net	36,338		23,177
Contingent consideration		13,292
Loans receivable, at fair value [Roll Forward]
Beginning balance	23,177	12,776
Transfers from held for sale	15,933	10,505
Principal payments received	(1,717)	(588)
Valuation adjustments	(1,055)	(313)
Ending balance	36,338	22,380
Fair Value Option, Differences Between Fair Values and Contractual Cash Flows	1055000	313000
Contingent Consideration Liability [Roll Forward]
Beginning balance	15,442	0
Additions	0	11,779
Valuation adjustments	1,264	1,513
Payout	(6,838)	0
Ending balance		13,292
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	0		0
Loans held for sale	0		0
Loans receivable, net	36,338		23,177
Other assets - derivatives	0		0
Total assets	36,338		23,177
Contingent consideration	9,868		15,442
Other liabilities - derivatives	0		0
Total liabilities	9,868		15,442
Contingent Consideration Liability [Roll Forward]
Beginning balance			15,442
Ending balance	9,868		15,442
Mortgage banking operations	0		0
Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,538,880		1,513,157
Loans held for sale	307,511		465,983
Loans receivable, net	36,338		23,177
Other assets - derivatives	19,503		11,183
Total assets	1,902,232		2,013,500
Contingent consideration	9,868		15,442
Other liabilities - derivatives	1,088		4,025
Total liabilities	10,956		19,467
Contingent Consideration Liability [Roll Forward]
Beginning balance			15,442
Ending balance	9,868		15,442
Mortgage banking operations	307,511		465,983
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	0		0
Loans held for sale	0		0
Loans receivable, net	0		0
Other assets - derivatives	0		0
Total assets	0		0
Contingent consideration	0		0
Other liabilities - derivatives	0		0
Total liabilities	0		0
Contingent Consideration Liability [Roll Forward]
Beginning balance			0
Ending balance	0		0
Mortgage banking operations	0		0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,538,880		1,513,157
Loans held for sale	307,511		465,983
Loans receivable, net	0		0
Other assets - derivatives	19,503		11,183
Total assets	1,865,894		1,990,323
Contingent consideration	0		0
Other liabilities - derivatives	1,088		4,025
Total liabilities	1,088		4,025
Contingent Consideration Liability [Roll Forward]
Beginning balance			0
Ending balance	0		0
Mortgage banking operations	307,511		465,983
MBS
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,343,181		1,308,838
MBS \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	0		0
MBS \| Fair Value, Measurements, Recurring [Member] \| Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	1,343,181		1,308,838
MBS \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	0		0
MBS \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale	$ 1,343,181		$ 1,308,838

cash paid contingent consideration

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This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares.

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This element represents the amount of any change, including any differences arising upon settlement, recognized during the reporting period in the value of an asset or assets, arising from an item of contingent consideration, recognized in a business combination.

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Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date.

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Amount of gain (loss) recognized in earnings, arising from assets measured at fair value on a recurring basis using unobservable inputs (level 3).

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Settlements 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.

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This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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Information regarding the differences between fair value and contractual cash flows.

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This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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