Quarterly report pursuant to Section 13 or 15(d)

Accounting for Investments in Qualified Affordable Housing Projects - Summary of Change in Accounting Principle on Statements of Cash Flows (Detail)

v2.4.1.9
Accounting for Investments in Qualified Affordable Housing Projects - Summary of Change in Accounting Principle on Statements of Cash Flows (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Cash flows from operating activities:    
Net income $ 11,054us-gaap_NetIncomeLoss $ 10,991us-gaap_NetIncomeLoss
Total adjustment in net income   12,274us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities
Net cash provided by operating activities (5,007)us-gaap_NetCashProvidedByUsedInOperatingActivities 23,265us-gaap_NetCashProvidedByUsedInOperatingActivities
Cash flows from investing activities:    
Net cash provided by investing activities 185,550us-gaap_NetCashProvidedByUsedInInvestingActivities 2,418us-gaap_NetCashProvidedByUsedInInvestingActivities
Cash flows from financing activities:    
Net cash used in financing activities (156,809)us-gaap_NetCashProvidedByUsedInFinancingActivities (656)us-gaap_NetCashProvidedByUsedInFinancingActivities
Net increase in cash and cash equivalents 23,734us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease 25,027us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
Cash and cash equivalents at beginning of year 158,320us-gaap_CashCashEquivalentsAndFederalFundsSold 179,357us-gaap_CashCashEquivalentsAndFederalFundsSold
Cash and cash equivalents at end of period 182,054us-gaap_CashCashEquivalentsAndFederalFundsSold 204,384us-gaap_CashCashEquivalentsAndFederalFundsSold
As Previously Reported [Member]    
Cash flows from operating activities:    
Net income   11,035us-gaap_NetIncomeLoss
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Total adjustment in net income   12,230us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Net cash provided by operating activities   23,265us-gaap_NetCashProvidedByUsedInOperatingActivities
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Cash flows from investing activities:    
Net cash provided by investing activities   2,418us-gaap_NetCashProvidedByUsedInInvestingActivities
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Cash flows from financing activities:    
Net cash used in financing activities   (656)us-gaap_NetCashProvidedByUsedInFinancingActivities
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Net increase in cash and cash equivalents   25,027us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Cash and cash equivalents at beginning of year   179,357us-gaap_CashCashEquivalentsAndFederalFundsSold
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Cash and cash equivalents at end of period   204,384us-gaap_CashCashEquivalentsAndFederalFundsSold
/ us-gaap_StatementScenarioAxis
= us-gaap_ScenarioPreviouslyReportedMember
Effect of Change in Accounting Principle [Member]    
Cash flows from operating activities:    
Net income   (44)us-gaap_NetIncomeLoss
/ us-gaap_StatementScenarioAxis
= us-gaap_RestatementAdjustmentMember
Total adjustment in net income   $ 44us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities
/ us-gaap_StatementScenarioAxis
= us-gaap_RestatementAdjustmentMember