v2.4.1.9
Earnings Per Share - Computation of Basic and Diluted Net Earnings (Loss) Per Share (Detail) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Numerator:                      
Net income $ 5,053us-gaap_NetIncomeLoss $ 11,063us-gaap_NetIncomeLoss $ 10,154us-gaap_NetIncomeLoss $ 10,854us-gaap_NetIncomeLoss $ 11,212us-gaap_NetIncomeLoss $ 13,802us-gaap_NetIncomeLoss $ 15,502us-gaap_NetIncomeLoss $ 6,395us-gaap_NetIncomeLoss $ 37,123us-gaap_NetIncomeLoss $ 46,910us-gaap_NetIncomeLoss $ 19,811us-gaap_NetIncomeLoss
Denominator:                      
Denominator for basic earnings per share – weighted average shares                 20,714us-gaap_WeightedAverageNumberOfSharesOutstandingBasic 20,676us-gaap_WeightedAverageNumberOfSharesOutstandingBasic 21,680us-gaap_WeightedAverageNumberOfSharesOutstandingBasic
Effect of dilutive securities:                      
Employee stock options (in shares)                 107us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements 88us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements 52us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements
Denominator for diluted earnings per share – weighted average shares                 20,821us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding 20,764us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding 21,732us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding