EXHIBIT A JOINT FILING AGREEMENT ---------------------- In accordance with Rule 13d-1(k)(l) under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing of the attached Schedule 13G, and any and all amendments thereto, and expressly authorize AMVESCAP PLC, as the ultimate parent company of each of its undersigned subsidiaries, to file such Schedule 13G, and any and all amendments thereto, on behalf of each of them.
Dated: February 13, 2006 AMVESCAP PLC By: /s/ Lisa Brinkley ---------------------------- Name: Lisa Brinkley Title: Chief Compliance Officer AIM Advisors, Inc. By: /s/ Lisa Brinkley ---------------------------- Name: Lisa Brinkley Title: Chief Compliance Officer AIM Capital Management, Inc. By: /s/ Lisa Brinkley ---------------------------- Name: Lisa Brinkley Title: Chief Compliance Officer AIM Funds Management, Inc. By: /s/ Lisa Brinkley ---------------------------- Name: Lisa Brinkley Title: Chief Compliance Officer AIM Private Asset Management, Inc. By: /s/ Lisa Brinkley ---------------------------- Name: Lisa Brinkley Title: Chief Compliance Officer AMVESCAP National Trust Company By: /s/ Kevin Lyman ---------------------------- Name: Kevin Lyman Title: General Counsel Atlantic Trust Company, N.A. By: /s/ Paul Elmlinger ---------------------------- Name: Paul Elmlinger Title: General Counsel INVESCO Hong Kong Limited By: /s/ Asha Balachandra ---------------------------- Name: Asha Balachandra Title: Reg. Head of Legal AP
INVESCO Asset Management GmbH By: /s/ Stephanie Ehrenfried ---------------------------- Name: Stephanie Ehrenfried Title: Head of Legal CE INVESCO Asset Management Limited By: /s/ Michelle Moran ---------------------------- Name: Michelle Moran Title: Head of Legal for UK and Ireland INVESCO Asset Management S.A. By: /s/ Stephanie Ehrenfried ---------------------------- Name: Stephanie Ehrenfried Title: Head of Legal CE INVESCO Asset Management Osterreich GmbH By: /s/ Stephanie Ehrenfried ---------------------------- Name: Stephanie Ehrenfried Title: Head of Legal CE INVESCO Global Asset Management (N.A.), Inc. By: /s/ Jeffrey Kupor ---------------------------- Name: Jeffrey Kupor Title: General Counsel INVESCO GT Management Company S.A. By: /s/ Nick Styman ---------------------------- Name: Nick Styman Title: Director of European Compliance INVESCO GT Management S.A. By: /s/ Nick Styman ---------------------------- Name: Nick Styman Title: Director of European Compliance INVESCO Institutional (N.A.), Inc. By: /s/ Jeffrey Kupor ---------------------------- Name: Jeffrey Kupor Title: General Counsel INVESCO Italia SGR SpA By: /s/ Stephanie Ehrenfried ---------------------------- Name: Stephanie Ehrenfried Title: Head of Legal CE INVESCO Maximum Income Management S.A. By: /s/ Nick Styman ---------------------------- Name: Nick Styman Title: Director of European Compliance INVESCO Private Capital, Inc. By: /s/ Jeffrey Kupor ---------------------------- Name: Jeffrey Kupor Title: General Counsel INVESCO Senior Secured Management, Inc. By: /s/ Jeffrey Kupor ---------------------------- Name: Jeffrey Kupor Title: General Counsel INVESCO Taiwan Limited By: /s/ Asha Balachandra ---------------------------- Name: Asha Balachandra Title: Reg. Head of Legal, AP INVESCO Asset Management (Japan) Limited By: /s/ Asha Balachandra ---------------------------- Name: Asha Balachandra Title: Reg. Head of Legal, AP INVESCO Asset Management Ireland Limited By: /s/ Michelle Moran ---------------------------- Name: Michelle Moran Title: Head of Legal for UK and Ireland INVESCO Kapitalanlagegesellschaft GmbH By: /s/ Stephanie Ehrenfried ---------------------------- Name: Stephanie Ehrenfried Title: Head of Legal CE Stein Roe Investment Counsel, Inc. By: /s/ Greg Campbell ---------------------------- Name: Greg Campbell Title: General Counsel