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Accumulated Other Comprehensive Income - Activity in Accumulated Other Comprehensive Income (Detail) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Sep. 30, 2014
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Sep. 30, 2013
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Sep. 30, 2014
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Sep. 30, 2013
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Sep. 30, 2014
Accumulated Net Unrealized Investment Gain (Loss) [Member]
|
Sep. 30, 2013
Accumulated Net Unrealized Investment Gain (Loss) [Member]
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Sep. 30, 2014
Accumulated Net Unrealized Investment Gain (Loss) [Member]
|
Sep. 30, 2013
Accumulated Net Unrealized Investment Gain (Loss) [Member]
|
Sep. 30, 2014
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Interest-Only Strip [Member]
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Sep. 30, 2014
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Interest-Only Strip [Member]
|
Sep. 30, 2013
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Interest-Only Strip [Member]
|
Jun. 30, 2013
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Interest-Only Strip [Member]
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Sep. 30, 2014
Tax (Expense) Benefit [Member]
|
Sep. 30, 2013
Tax (Expense) Benefit [Member]
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Sep. 30, 2014
Tax (Expense) Benefit [Member]
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Sep. 30, 2013
Tax (Expense) Benefit [Member]
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| Accumulated Other Comprehensive Income [Line Items] | ||||||||||||||||
| Balance at beginning of period | $ (2,150) | $ 1,634 | $ (9,380) | $ 5,418 | $ (5,534) | $ 915 | $ (18,187) | $ 7,348 | $ 17 | $ 16 | $ 16 | $ 17 | $ 3,367 | $ 702 | $ 8,791 | $ (1,946) |
| Other comprehensive (loss) income before reclassification | (2,848) | (5,492) | 6,167 | (8,964) | (4,947) | (10,020) | 9,491 | (16,141) | (3) | (2) | 1 | 2,102 | 4,528 | (3,322) | 7,176 | |
| Reclassification from accumulated other comprehensive income | (67) | (611) | (1,852) | (923) | (67) | (611) | (1,852) | (923) | ||||||||
| Other comprehensive (loss) income | (2,915) | (6,103) | 4,315 | (9,887) | (5,014) | (10,631) | 7,639 | (17,064) | (3) | (2) | 1 | 2,102 | 4,528 | (3,322) | 7,176 | |
| Balance at end of period | $ (5,065) | $ (4,469) | $ (5,065) | $ (4,469) | $ (10,548) | $ (9,716) | $ (10,548) | $ (9,716) | $ 14 | $ 14 | $ 17 | $ 17 | $ 5,469 | $ 5,230 | $ 5,469 | $ 5,230 |