Other Long-term Debt - Summary of Other Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt	$ 89,459us-gaap_OtherLongTermDebt	$ 144,385us-gaap_OtherLongTermDebt
Borrowings from FHLB [Member]
Debt Instrument [Line Items]
2013, Weighted Average Contractual Rate		1.13%
2013, Weighted Average Effective Rate		1.13%
2013, Amount		57,892
2014, Weighted Average Contractual Rate	0.82%	0.82%
2015, Weighted Average Contractual Rate	3.82%	4.64%
2016, Weighted Average Contractual Rate	3.83%	4.64%
2017, Weighted Average Contractual Rate	3.83%	4.64%
2018, Weighted Average Contractual Rate	3.84%
Thereafter, Weighted Average Contractual Rate		4.66%
Thereafter, Weighted Average Contractual Rate	3.81%
2014, Weighted Average Effective Rate	0.82%	0.82%
2015, Weighted Average Effective Rate	3.82%	4.64%
2016, Weighted Average Effective Rate	3.83%	4.64%
2017, Weighted Average Effective Rate	3.83%	4.64%
2018, Weighted Average Effective Rate	3.84%
Thereafter, Weighted Average Effective Rate		4.66%
Thereafter, Weighted Average Effective Rate	3.81%
2014, Amount	80,142	79,971
2015, Amount	563	389
2016, Amount	585	407
2017, Amount	607	426
2018, Amount	631
Thereafter, Amount		5,300
Thereafter, Amount	$ 6,931

Long Term Debt Maturities Repayments Of Principal After Year Six

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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