INCOME TAXES - Significant Components of Deferred Taxes (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Net operating loss carryforward	$ 40,073	$ 32,734
Recognized built-in loss carryforward	7,580	6,570
Acquisition accounting fair value adjustments	12,229	12,330
Allowance for loan losses	2,990	2,499
Federal tax credits carryforward	3,140	1,282
Unrealized losses on securities	667	4,109
Unrealized losses on cash flow hedges	728	0
Stock-based compensation	2,094	1,808
Capitalized leases	1,167crfn_DeferredTaxAssetsLeases	0crfn_DeferredTaxAssetsLeases
Deferred compensation	3,024	117
Other	2,942us-gaap_DeferredTaxAssetsOther	497us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	76,634us-gaap_DeferredTaxAssetsGross	61,946us-gaap_DeferredTaxAssetsGross
Valuation allowance	(1,185)	(5,130)
Deferred tax asset, net	75,449us-gaap_DeferredTaxAssetsNet	56,816us-gaap_DeferredTaxAssetsNet
Deferred tax liabilities:
Unrealized gains on cash flow hedges	0	1,490
Premises and equipment	2,568	203
Prepaid expenses	478	256
Total deferred tax liabilities	3,046us-gaap_DeferredIncomeTaxLiabilities	1,949us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset	$ 72,403us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 54,867us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Assets, Leases

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the provision for loan losses.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from unrealized losses on trading securities.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from derivatives.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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