Financing Agreements - Additional Information (Detail) (USD $) | 6 Months Ended | | | | | 0 Months Ended | | 0 Months Ended | | | 6 Months Ended | | 0 Months Ended | | 0 Months Ended | | | | | 0 Months Ended | | | 0 Months Ended | |
In Thousands, unless otherwise specified | Jun. 30, 2014 | Jun. 30, 2013 | Dec. 31, 2013 | Aug. 31, 2009 | Mar. 22, 2012 | Mar. 22, 2012 | Mar. 22, 2012 | Jun. 30, 2014 | Mar. 22, 2012 | Mar. 22, 2012 | Mar. 22, 2012 | Mar. 22, 2012 | Mar. 22, 2012 | Jun. 30, 2014 | Jun. 30, 2014 | Mar. 22, 2012 | Jun. 30, 2014 | Dec. 31, 2007 | Jun. 30, 2014 | Aug. 31, 2009 | Mar. 22, 2012 | Mar. 22, 2012 | Mar. 22, 2012 | Mar. 22, 2012 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2007 | Jun. 30, 2014 | Mar. 22, 2012 | Mar. 22, 2012 | Jun. 30, 2014 | Jun. 30, 2014 | Jun. 30, 2014 | Aug. 31, 2009 | Mar. 22, 2012 | Mar. 22, 2012 |
| Amended and Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | London Interbank Offered Rate (LIBOR) | London Interbank Offered Rate (LIBOR) | London Interbank Offered Rate (LIBOR) | London Interbank Offered Rate (LIBOR) | London Interbank Offered Rate (LIBOR) | London Interbank Offered Rate (LIBOR) | Prime Lending Rate | Federal Funds Rate | Federal Funds Rate | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Senior Unsecured Revolving Credit Facility | Term Loan Facility | Term Loan Facility | Term Loan Facility | Term Loan Facility | Term Loan Facility | Term Loan Facility |
| | | Minimum | Maximum | | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | | | Second Amended Restated Credit Agreement | | | Amended and Restated Credit Agreement | Amended and Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | China HR Credit Facility | China HR Credit Facility | Letter of Credit | Letter of Credit | Letter of Credit | Letter of Credit | Third Quarter | Fourth Quarter | Amended and Restated Credit Agreement | Amended and Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement |
| | | | | | | Minimum | Minimum | Maximum | Maximum | | | | | | | | | | Minimum | Maximum | | | | Amended and Restated Credit Agreement | Second Amended Restated Credit Agreement | Second Amended Restated Credit Agreement | | | | | | |
| | | | | | | Scenario 1 | Scenario 2 | Scenario 1 | Scenario 2 | | | | | | | | | | | | | | | | Minimum | Maximum | | | | | | |
Line of Credit Facility [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Maximum borrowings under senior unsecured revolving credit facility | ' | ' | ' | $300,000 | $325,000 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $250,000 | ' | $250,000 | ' | $225,000 | ' | ' | $5,049 | $7,574 | $50,000 | ' | ' | ' | ' | ' | ' | $50,000 | ' | $100,000 |
Payments on borrowings on credit facilities | 8,100 | 39,799 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 172,500 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Payments on borrowings on term note | 4,375 | 3,125 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 40,000 | ' |
Debt instrument maturity date | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 22-Mar-15 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 22-Mar-15 | ' |
Amortization payments on outstanding principal amount of term loans, in next twelve months | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 2,500 | 2,500 | ' | ' | ' | ' |
Debt instrument, basis spread on variable rate | ' | ' | ' | ' | ' | ' | ' | ' | 1.00% | 2.50% | 1.50% | 3.25% | 2.25% | ' | ' | 0.50% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Fee on all outstanding amounts of letters of credit | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 2.50% | 3.25% | ' | ' | ' | ' | ' | ' |
Commitment fee on the unused portion of the revolving credit facility | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 0.35% | 0.50% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Consolidated Leverage Ratio | ' | ' | ' | ' | ' | ' | 300.00% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Interest Charge Coverage Ratio | ' | ' | ' | ' | ' | 300.00% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Utilized portion of credit facility | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 116,600 | ' | ' | ' | ' | ' | ' | ' | ' | 309 | ' | ' | ' | ' | 85,000 | ' | ' | ' |
Credit facility due to mature | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 22-Mar-15 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Current portion of long-term debt and borrowings on revolving credit facilities | 201,600 | ' | 9,375 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 201,600 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Credit facility, available to be utilized | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | $108,091 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Interest rate at the end of period | ' | ' | ' | ' | ' | ' | ' | 0.16% | ' | ' | ' | ' | ' | 3.25% | 0.09% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Interest rate at the end of period, effective | ' | ' | ' | ' | ' | ' | ' | 3.15% | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |